diff --git a/CHANGELOG.md b/CHANGELOG.md
index abc858022..a3e4940a3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,11 +2,60 @@
## Unreleased
+* target Android 15
+* improve readability of info messages in dark mode
+* fix Direct Share shortcuts
+
+## v2.11.0
+2025-08
+
+* add "After 1 year" option to disappearing messages
+* improve image quality when setting group avatars
+* add Estonian translation, update other translations
+* allow to clone email chats
+* fix some small bugs
+* update to core 2.11.0
+
+## v2.10.0
+2025-08
+
+* fix "Archived" item's layout in chat-list
+* don't enlarge "Saved Messages" and "Devices Messages" avatars on click
+* share email address for email contacts instead of vCard
+* open existing encrypted chat when opening a mailto link or clicking an email address in a message bubble
+* update to core 2.10.0
+
+## v2.9.0
+2025-07
+
+* hide contact email addresses in search results
+* disable non-functional message editing and ephemeral messages timer settings in classic email thread chat
+* don't enlarge email chats avatar placeholder
+* improve message date/status footer layout, also in RTL languages
+* display correct text when receiving a "Disappearing messages enabled" system message
+* Update to core 2.9.0
+
+## v2.8.0
+2025-07
+
+* Profiles focus on recognizing contacts
+* See the number of media directly in the profile, no need to tap around
* Clearer app lists by removing redundant "App" subtitle
* New button for quick access to the apps sent in current chat
* New icon for the in-chat apps button
* Improve hint for app drafts
* Add Text-To-Speech (TTS) support for in-chat apps
+* New icon for the QR icon
+* Start rebuilding the experimental broadcast lists
+ into proper channels - note that this is work-in-progress
+* Improved separation between unencrypted chats/contacts and encrypted ones, avoiding mixing of encrypted and unencrypted messages in the same chat
+* Removed padlocks, as encrypted is the default "normal" state. Instead, unencrypted email is marked with a small email / letter (✉️) icon
+* Classic email chats/threads get a big email / letter icon making it easy to recognize
+* After some time, add a device message asking to donate. Can't wait? Donate today at https://delta.chat/donate
+* Allow to sort profiles up in the profile switcher
+* Add new option to create unencrypted email thread
+* Green checkmarks are removed where they mostly refer to guaranteed encryption, which is the default now. They are still used for profile's "Introduced by"
+* Update to core 2.8.0
## v1.58.4
2025-05
diff --git a/build.gradle b/build.gradle
index effdc6bcd..dd4709a03 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,5 +1,5 @@
plugins {
- id 'com.android.application' version '8.5.2'
+ id 'com.android.application' version '8.11.1'
id 'com.google.gms.google-services' version '4.4.1'
}
@@ -15,7 +15,7 @@ repositories {
android {
namespace "org.thoughtcrime.securesms"
flavorDimensions "none"
- compileSdk 34
+ compileSdk 35
// Set NDK version to strip native libraries.
// Even though we compile our libraries outside Gradle with `scripts/ndk-make.sh`,
@@ -27,14 +27,14 @@ android {
useLibrary 'org.apache.http.legacy'
defaultConfig {
- versionCode 722
- versionName "1.58.4"
+ versionCode 730
+ versionName "2.11.0"
applicationId "com.b44t.messenger"
multiDexEnabled true
minSdkVersion 21
- targetSdkVersion 34
+ targetSdkVersion 35
vectorDrawables.useSupportLibrary = true
@@ -149,9 +149,9 @@ android {
dependencies {
implementation 'androidx.sharetarget:sharetarget:1.2.0'
- implementation 'androidx.webkit:webkit:1.12.1'
+ implementation 'androidx.webkit:webkit:1.14.0'
implementation 'androidx.multidex:multidex:2.0.1'
- implementation 'androidx.appcompat:appcompat:1.7.0'
+ implementation 'androidx.appcompat:appcompat:1.7.1'
implementation 'com.google.android.material:material:1.12.0'
implementation 'androidx.legacy:legacy-support-v13:1.0.0'
implementation ('androidx.preference:preference:1.2.1') {
@@ -159,7 +159,7 @@ dependencies {
exclude group: 'androidx.lifecycle', module:'lifecycle-viewmodel-ktx'
}
implementation 'androidx.legacy:legacy-preference-v14:1.0.0'
- implementation 'androidx.exifinterface:exifinterface:1.3.7'
+ implementation 'androidx.exifinterface:exifinterface:1.4.1'
implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
implementation 'androidx.lifecycle:lifecycle-common-java8:2.6.2'
implementation 'androidx.lifecycle:lifecycle-viewmodel:2.6.2'
@@ -174,51 +174,47 @@ dependencies {
implementation ('com.journeyapps:zxing-android-embedded:4.3.0') { transitive = false } // QR Code scanner
implementation 'com.fasterxml.jackson.core:jackson-databind:2.11.1' // used as JSON library
implementation 'com.google.code.gson:gson:2.12.1' // used as JSON library.
- implementation "me.leolin:ShortcutBadger:1.1.16" // display messagecount on the home screen icon.
- implementation 'com.jpardogo.materialtabstrip:library:1.0.9' // used in the emoji selector for the tab selection.
implementation 'com.github.Baseflow:PhotoView:2.3.0' // does the zooming on photos / media
- implementation 'com.github.penfeizhou.android.animation:awebp:3.0.2' // animated webp support.
+ implementation 'com.github.penfeizhou.android.animation:awebp:3.0.5' // animated webp support.
implementation 'com.caverock:androidsvg-aar:1.4' // SVG support.
- implementation 'com.github.bumptech.glide:glide:4.12.0'
- annotationProcessor 'com.github.bumptech.glide:compiler:4.12.0'
+ implementation 'com.github.bumptech.glide:glide:4.16.0'
+ annotationProcessor 'com.github.bumptech.glide:compiler:4.16.0'
annotationProcessor 'androidx.annotation:annotation:1.9.1'
- implementation 'com.makeramen:roundedimageview:2.1.0' // crops the avatars to circles
- implementation 'com.pnikosis:materialish-progress:1.5' // used only in the "Progress Wheel" in Share Activity.
+ implementation 'com.makeramen:roundedimageview:2.3.0' // crops the avatars to circles
implementation 'com.github.amulyakhare:TextDrawable:558677ea31' // number of unread messages,
// the one-letter circle for the contacts (when there is not avatar) and a white background.
implementation 'com.googlecode.mp4parser:isoparser:1.0.6' // MP4 recoding; upgrading eg. to 1.1.22 breaks recoding, however, i have not investigated further, just reset to 1.0.6
- implementation ('com.davemorrissey.labs:subsampling-scale-image-view:3.6.0') { // for the zooming on photos / media
+ implementation ('com.davemorrissey.labs:subsampling-scale-image-view:3.10.0') { // for the zooming on photos / media
exclude group: 'com.android.support', module: 'support-annotations'
}
- implementation 'com.annimon:stream:1.1.8' // brings future java streams api to SDK Version < 24
// Replacement for ContentResolver
// that protects against the Surreptitious Sharing attack.
//
@@ -90,7 +87,7 @@
Autocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -970,7 +902,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1035,10 +965,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -If you don’t need a longer-lived copy of your messages on the server, -you can also turn on “delete messages from server automatically”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1755,19 +1621,19 @@ Nicméně, někteří poskytovatelé vyžadují ke správnému chodu speciální podrobnější popis je na Provider Overview
Autocrypt wird verwendet, um automatisch
-eine Ende-zu-Ende-Verschlüsselung mit Kontakten und Gruppenchats herzustellen.
-Autocrypt verwendet eine begrenzte und sichere Untermenge des OpenPGP-Standards.
-Ende-zu-Ende-verschlüsselte Nachrichten sind mit einem Vorhängeschloss gekennzeichnet
Delta Chat verwendet eine sichere Teilmenge des OpenPGP-Standards, um eine automatische End-to-End-Verschlüsselung mit folgenden Protokollen bereitzustellen:
-Secure-Join-Protokolle
-werden für Chats mit garantierter Ende-zu-Ende-Verschlüsselung verwendet,
-die vor Netzwerkangriffen und kompromittierten Servern schützt.
-Chats, die mit einem grünen Häkchen markiert sind
-
-garantieren Ende-zu-Ende-verschlüsselte Nachrichten.
Secure-Join +zum Austausch von Verschlüsselungsinformationen durch Scannen von QR-Codes oder „Einladungslinks“.
+Autocrypt wird verwendet, um automatisch eine Ende-zu-Ende-Verschlüsselung zwischen Kontakten und allen Mitgliedern einer Gruppe herzustellen.
+Teilen eines Kontakts im Chat +ermöglicht es den Empfängern, eine Ende-zu-Ende-Verschlüsselung mit dem Kontakt zu verwenden.
+Delta Chat fragt keine OpenPGP-Keyserver ab, veröffentlicht dort keine Daten und interagiert auch sonst nicht mit diesen.
Ende-zu-Ende-verschlüsselten Nachrichten sind mit einem Vorhängeschloss versehen:
- -Die Ende-zu-Ende-Verschlüsselung ist garantiert, wenn neben dem Chat-Titel ein grünes Häkchen zu sehen ist:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-Wenn Sie einen zweiten Kommunikationskanal mit Ihrem Chatpartner haben, -wie einen Video-Chat oder einen anderen Messenger, -können Sie einen Einladungslink erstellen.
+Wenn Sie die Standard-Chatmail-Relays verwenden, ist es unmöglich, Nachrichten ohne End-to-End-Verschlüsselung zu empfangen oder zu senden.
-Wenn Sie persönlich zusammen sind, -können Sie Ihrem Chat-Partner einen QR-Code zeigen.
+Wenn Sie stattdessen ein Profil mit einem klassischen E-Mail-Server erstellen,
+können Sie Nachrichten ohne End-to-End-Verschlüsselung senden und empfangen.
+Solche Nachrichten werden mit einem E-Mail-Symbol gekennzeichnet
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
Für Direktchat-Einladungen,
-tippen Sie auf das QR-Code-Symbol
-auf dem Hauptbildschirm der Delta-Chat-App.
For direct 1:1 chat invitations,
+tap the QR Code icon
+on the Delta Chat app main screen.
Lassen Sie Ihren Chat-Partner den QR-Code mit der Delta-Chat-App scannen. -Oder Sie klicken auf „Kopieren“ oder „Teilen“, um einen Einladungslink zu erstellen und diesen mit Ihrem Chat-Partner zu teilen.
+Ask your chat partner to scan the QR image +with their Delta Chat app, +or click “Copy” or “Share” to create an invite link +and share it with your chat partner.
-Warten Sie nun, während das Secure-Join-Protokoll zwischen beiden Geräten abläuft.
+Now wait while end-to-end encryption is getting established.
Wenn beide Geräte online sind,
-sehen beide Seiten schließlich einen Gruppen- oder Direkt-Chat mit einem grünen Häkchen
-
-neben dem Titel.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
Wenn eines der Geräte offline ist, erscheinen die grünen Häkchen erst -später, wenn das Gerät wieder mit dem Internet verbunden ist -und das Secure-Join-Protokoll abgeschlossen werden kann.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Herzlichen Glückwunsch! 🎉
-Sie verwenden nun eine garantierte Ende-zu-Ende-Verschlüsselung
-mit diesem Kontakt und Sie beide können sich gegenseitig zu grün markierten Gruppen hinzufügen
-,
-Dadurch wird die garantierte Ende-zu-Ende-Verschlüsselung automatisch unter den Mitgliedern dieser Gruppe verbreitet.
Congratulations! +You now will automatically use end-to-end encryption +with this contact. +If you add each other to chat groups, +end-to-end encryption will be established among all members.
Chat-Titel mit grünen Häkchen +
A contact profile might show a green checkmark
-bedeuten, dass alle Nachrichten im Chat Ende-zu-Ende-verschlüsselt werden
-und nicht von kompromittierten E-Mail-Servern oder Internet-Providern gelesen oder verändert werden können.
-Beim Beitritt zu Gruppenchats mit grünen Häkchen
-werden Verschlüsselungsinformationen (und die grünen Häkchen) aller Teilnehmer sicher so weitergegeben,
-dass die Ende-zu-Ende-Verschlüsselung in der Gruppe und zwischen den Mitgliedern garantiert werden kann.
Kontaktprofile mit grünen Häkchen
-
-bedeuten, dass die Nachrichtenübermittlung an einen Kontakt derzeit garantiert Ende-zu-Ende-verschlüsselt ist.
-Jeder grün markierte Kontakt hat entweder einen direkten QR-Scan mit Ihnen durchgeführt
-oder wurde von einem anderen Kontakt mit grünem Häkchen eingeführt.
-Das Einführen geschieht automatisch, wenn Sie Mitglieder zu Gruppen hinzufügen.
-Wer einen Kontakt zu einer Gruppe mit grünem Häkchen hinzufügt, wird zum Einführenden
-für die Mitglieder, die noch nichts von dem hinzugefügten Kontakt wussten.
-In einem Kontaktprofil können Sie wiederholt auf den Text “Eingeführt von …” tippen
-bis Sie zu demjenigen gelangen, mit dem Sie einen direkten QR-Scan gemacht haben.
Beachten Sie, dass Sie in einem Kontaktprofil unter Umständen Einführende sehen und antippen können, aber kein grünes Häkchen im Profiltitel vorhanden ist. -Dies bedeutet normalerweise, dass der Kontakt “eine Nachricht von einem anderen Gerät gesendet hat”.
+and an “Introduced by” line. +Every green-checkmarked contact either did a direct QR-scan with you +or was introduced by a another green-checkmarked contact. +Introductions happen automatically when adding members to groups. +Whoever adds a green-checkmarked contact to a group with only green-checkmarked members +becomes an introducer. +In a contact profile you can tap on the “Introduced by …” text repeatedly +until you get to the one with whom you directly did a QR-scan.Für eine ausführlichere Diskussion der “Garantierten Ende-zu-Ende-Verschlüsselung”, siehe Secure-Join-Protokolle und dort speziell den Abschnitt zu “Verified Groups”, dem technischen Begriff für “Chats mit grünem Häkchen” oder “Garantierter Ende-zu-Ende-Verschlüsselung”.
-Wenn Sie diese Warnung sehen, wurde das grüne Häkchen entfernt, da für den Kontakt die Ende-zu-Ende-Verschlüsselung nicht mehr garantiert werden kann. -Wenn Sie den Wegfall der garantierten Ende-zu-Ende-Verschlüsselung -für diesen Kontakt überraschend finden, akzeptieren Sie die Warnung nicht! -Versuchen Sie stattdessen mit Ihrem Kontakt über einen zweiten Kanal (z.B. Videoanruf, Telefon oder ein anderer Messenger) herauszufinden, was passiert ist.
- -Wenn Ihr Kontakt tatsächlich den Ausfall der garantierten Ende-zu-Ende-Verschlüsselung verursacht hat, -finden Sie in den nächsten Abschnitten häufige Gründe und Abhilfe. -Unabhängig davon bleiben alle anderen Chats mit einem grünen Häkchen garantiert Ende-zu-Ende-verschlüsselt, -auch wenn der Kontakt dort Mitglied ist.
- -Ihr Kontakt verwendet Delta Chat auf einem zweiten Gerät (Smartphone oder Laptop)
- -Wenn Ihr Kontakt ein weiteres Gerät mit Delta Chat eingerichtet hat, -sollte das Konto von dem neuen Gerät entfernen werden und als zweites Gerät, wie hier beschrieben, erneut hinzugefügt werden. -Sobald sie sich danach schreiben, wird die Warnung verschwinden -und die Verschlüsselung ist mit beiden Geräten Ihres Kontakts garantiert.
- -Ihr Kontakt hat Delta Chat mit seinem alten Login neu installiert
- -Wenn Ihr Kontakt ein Backup hat, -sollte das Profil auf dem neuen Gerät -entfernt werden und stattdessen das Backup importiert werden, um das Konto neu zu erstellen. -Sobald sie sich danach schreiben, wird die Warnung verschwinden -und die garantierte Verschlüsselung wird für diesen Kontakt wiederhergestellt.
- -Wenn Ihr Kontakt kein Backup hat, ist es am besten, einen QR-Code-Scan -mit Ihrem Chat-Partner durchzuführen, um die garantierte Ende-zu-Ende-Verschlüsselung wiederherzustellen.
- -Ihr Kontakt hat eine E-Mail über Webmail oder eine andere E-Mail-Anwendung gesendet, -wird Delta Chat aber bald wieder benutzen.
- -Wenn Sie wissen, dass der Kontakt manchmal Webmail, -oder andere E-Mail-Anwendungen ohne Ende-zu-Ende-Verschlüsselung verwendet, -dann können Sie die Warnung akzeptieren. -Sobald Ihr Kontakt Delta Chat wieder benutzt, -wird die garantierte Ende-zu-Ende-Verschlüsselung automatisch wiederhergestellt.
- -Ihr Kontakt hat die Nutzung von Delta Chat komplett eingestellt
- -Manchmal ist es wichtiger, in Kontakt zu bleiben als eine Ende-zu-Ende-Verschlüsselung zu haben; -die “Transport Layer Encryption” (TLS) kann die Vertraulichkeit -Ihrer Nachrichten zwischen Ihrem Gerät und dem E-Mail-Server dennoch schützen. -Ohne Ende-zu-Ende-Verschlüsselung vertrauen Sie und Ihr Chat-Partner jedoch darauf, dass Ihr E-Mail-Server Nachrichten nicht liest oder manipuliert und sie nicht an Dritte weitergibt.
- -In jedem Fall können Sie nicht viel mehr tun, als die Warnung zu akzeptieren. -Bitte entfernen Sie den Kontakt auch aus allen aktiven, grün markierten Gruppen -die Sie unter “Gemeinsame Chats” im Profil des Kontakts finden können. -So vermeiden Sie, dass Ihr Kontakt “unlesbare” Nachrichten erhält.
- -Wenn der Kontakt Delta Chat aufgrund von Fehlern oder Bugs nicht mehr verwendet, -können Sie diese in unser Support-Forum schreiben, -und uns so dabei helfen, häufige Probleme zu identifizieren und zu lösen. Vielen Dank!
-Ja, Delta Chat verwendet eine sichere Untermenge von OpenPGP -und zeigt nur dann ein Vorhängeschloss auf einer Nachricht an, -wenn die gesamte Nachricht ordnungsgemäß verschlüsselt und signiert ist. -Zum Beispiel werden “Detached Signatures” nicht als sicher betrachtet.
+Yes, Delta Chat uses a secure subset of OpenPGP +requiring the whole message to be properly encrypted and signed. +For example, “Detached signatures” are not treated as secure.
Die meisten öffentlich diskutierten OpenPGP-Probleme resultieren in Wirklichkeit aus schlechter Usability oder schlechter Implementierung von Tools oder Anwendungen - oder beidem. @@ -961,16 +898,15 @@ so wie in der Autocrypt-Level-1-Spezifikation definiert.
Auch wenn Ihre Nachrichten nicht Ende-zu-Ende-verschlüsselt sind, -sind sie dennoch vor Internetanbietern wie Mobilfunk- oder Telefongesellschaften geschützt. -Allerdings können Ihr E-Mail-Provider und der des Empfängers -Ihre Nachrichten lesen, analysieren oder sogar verändern, -wenn sie nicht Ende-zu-Ende-verschlüsselt sind.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat verwendet standardmäßig strikte TLS-Verschlüsselung, @@ -982,10 +918,6 @@ Wenn die beteiligten E-Mail-Server Beibehaltung der garantierten Ende-zu-Ende-Verschlüsselung zusätzlich zur TLS-Verschlüsselung -eine allumfassende Sicherheit zwischen Ihrem Gerät und dem des Empfängers bietet. -Nicht einmal Ihr E-Mail- oder Internet-Provider wird in der Lage sein, Ihre Nachrichten zu lesen oder zu verändern.
Delta Chat schützt die meisten Metadaten von Nachrichten, indem es die folgenden Informationen -in den Ende-zu-Ende-verschlüsselten Teil der Nachrichten verschiebt:
+Anders als die meisten anderen Messenger +speichern Delta-Chat-Apps keine Metadaten über Kontakte oder Gruppen auf Servern. Auch nicht in verschlüsselter Form. +Stattdessen werden alle Gruppen-Metadaten durchgängig verschlüsselt und ausschließlich auf den Endgeräten der Nutzer gespeichert.
+ +E-Mail-Server können deshalb nur das Folgende sehen:
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
-HeaderUhrzeit und Datum der Nachricht
+Absende- und Empfangsadresse
+Größe der Nachricht
+E-Mail-Server erhalten keinen Zugriff auf diese geschützten Metadaten, -sehen aber Datum und Größe der Nachricht sowie die Absender- und Empfängeradressen. -E-Mail-Server benötigen Empfängeradressen, um Nachrichten -Nachrichten an die Geräte der Empfänger weiterzuleiten und zuzustellen.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Sowohl zum Schutz vor E-Mail-Servern, die Metadaten sammeln, -als auch gegen die Gefahr der Beschlagnahmung von Geräten -empfehlen wir die Verwendung einer für Delta Chat optimierten E-Mail-Server-Instanz, um pseudonym-temporäre Konten durch Scannen von QR-Codes zu erstellen. -Beachten Sie, dass Delta-Chat-Apps auf allen Plattformen mehrere Konten unterstützen. -Sie können also problemlos aktionsspezifische “1-Wochen-“ oder “1-Monats-Konten” neben Ihrem “Hauptkonto” verwenden, -mit dem Wissen, dass alle temporären Kontodaten zusammen mit allen Metadaten gelöscht werden. -Wenn ein Gerät beschlagnahmt wird, können Kontakte mit temporären E-Mail-Konten -Konten nicht so leicht identifiziert werden, wie dies bei Messengern der Fall ist, die die -Telefonnummern in Chatgruppen preisgeben, die wiederum oft mit legalen Identitäten verbunden sind.
+Both for protecting against metadata-collecting e-mail servers +as well as against the threat of device seizure +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. +Note that Delta Chat apps on all platforms support multiple profiles +so you can easily use situation-specific profiles next to your “main” profile +with the knowledge that all their data, along with all metadata, will be deleted. +Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily.
-Sie können den Status der Ende-zu-Ende-Verschlüsselung manuell im Dialog “Verschlüsselung” -(Android/iOS: Benutzerprofil, Desktop: Rechtsklick auf den Chat eines Benutzers) überprüfen. -Delta Chat zeigt dort zwei Fingerabdrücke an. -Wenn die gleichen Fingerabdrücke auf Ihrem eigenen Gerät und auf dem Gerät Ihres Kontakts erscheinen, -ist die Verbindung sicher.
- -No, not yet.
-Ein kleines Vorhängeschloss in einer Nachrichten zeigt an, -dass die Nachricht vom Absender korrekt Ende-zu-Ende-verschlüsselt wurde. -Wenn kein Vorhängeschloss vorhanden ist, wurde die Nachricht nicht oder nicht korrekt Ende-zu-Ende-verschlüsselt. -Höchstwahrscheinlich, weil der Absender ein Webmail-Interface oder eine App -ohne Ende-zu-Ende-Unterstützung verwendet.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-Wenn ein Kontakt keine Autocrypt-fähige App verwendet, -werden alle Nachrichten, die diesen Kontakt betreffen (in Gruppen- oder Direkt-Chats), -nicht Ende-zu-Ende-verschlüsselt und zeigen daher kein “Vorhängeschloss”. -Beachten Sie, auch Kontakte, die primär Delta Chat verwenden, -können gleichzeitig auch nicht-Autocrypt-fähige Apps verwenden. -Das unverschlüsselte Antworten auf unverschlüsselte Nachrichten wird von Autocrypt vorgeschrieben -um zu verhindern, dass unlesbare Nachrichten auf der Seite Ihrer Kontakte ankommen.
- -Wenn Sie einen sicheren Ende-zu-Ende-verschlüsselten Chat mit einem Kontakt benötigen, -der sowohl Delta Chat als auch Nicht-Autocrypt-Anwendungen nutzt, -können Sie eine garantierte Ende-zu-Ende-Verschlüsselung einrichten, mit einer Gruppe mit Ihnen beiden als Mitgliedern. -In diesem Gruppenchat werden alle Nachrichten Ende-zu-Ende verschlüsselt werdejn, -auch wenn im Direkt-Chat eine -“Nachricht von einem anderen Gerät gesendet” wurde.
- -Der beste Weg, um sicherzustellen, dass alle Nachrichten Ende-zu-Ende-verschlüsselt sind -und Metadaten so schnell wie möglich gelöscht werden, -ist die Verwendung von Chats mit garantierter Ende-zu-Ende-Verschlüsselung -und die Aktivierung von verschwindenden Nachrichten.
- -Garantierte Ende-zu-Ende-Verschlüsselung schützt vor MITM-Angriffen -und das Aktivieren von “Verschwindende Nachrichten” löscht die Nachrichten -auf dem Server und Lokal nach einer vom Benutzer eingestellten Zeit.
- -Wenn Sie die Nachrichten auf Ihrem Gerät, aber nicht auf dem Server benötigen, können Sie auch in der Gruppe vereinbaren, “Nachrichten automatisch vom Server löschen” einzuschalten.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
Nein, Delta Chat unterstützt kein “Perfect Forward Secrecy” (PFS). -Das bedeutet, wenn Ihr privater Delta-Chat-Schlüssel durchgesickert ist -und jemand Ihre vorherigen In-Transit-Nachrichten gesammelt hat, -können diese mit dem veröffentlichtem Schlüssel entschlüsselt werden.
+No, not yet.
-Beachten Sie jedoch, dass jemand, der in den Besitz Ihrer privaten Schlüssel gelangt, in der Regel auch in der Lage sein wird, Ihre Nachrichten zu lesen - unabhängig davon, ob Perfect Forward Secrecy nun verwendet wird oder nicht. -Die typische, reale Situation für durchgesickerte private Schlüssel, ist die Beschlagnahme von Geräten.
+Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, +and someone has collected your prior in-transit messages, +they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages.
-Es ist möglich, dass Delta Chat eine Tages “Perfect Forward Secrecy” unterstützt - -OpenPGP ist nur ein Container für verschlüsselte Nachrichten mit dem -die Verwaltung der Schlüssel (und damit die Schlüsselrotation oder das Schlüssel-“Ratcheting”) -auf flexible Weise organisiert werden kann. -Siehe Seqouias PFS-Prototyp -für bestehende Experimente in der OpenPGP-Community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-Das hängt davon ab, was für Sie wichtig ist. -Delta Chat unterstützt kein PFS, -bietet aber garantierte Ende-zu-Ende-Verschlüsselung, -die vor kompromittierten Servern oder korrupten Netzwerken schützt. -Signal und die meisten anderen PFS-unterstützenden Messenger bieten kein -praktisches System zum Schutz von Chatgruppen vor Netzwerkangriffen. -Diese sind besorgniserregender und realer -als ein potenzieller Angreifer, der zwar Ihr Telefon und Ihre privaten Schlüssel beschlagnahmt, -aber irgendwie nicht Ihre Nachrichten - gleichzeitig aber eine vollständige Aufzeichnung aller -vergangenen verschlüsselten Nachrichten hat.
+No, not yet.
-In jedem Fall verwendet die Ende-zu-Ende-Verschlüsselung von Delta Chat eine sichere Untermenge von OpenPGP -das unabhängig sicherheitsgeprüft wurde.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +Sie können den Status der Ende-zu-Ende-Verschlüsselung manuell im Dialog “Verschlüsselung” +(Android/iOS: Benutzerprofil, Desktop: Rechtsklick auf den Chat eines Benutzers) überprüfen. +Delta Chat zeigt dort zwei Fingerabdrücke an. +Wenn die gleichen Fingerabdrücke auf Ihrem eigenen Gerät und auf dem Gerät Ihres Kontakts erscheinen, +ist die Verbindung sicher.
Mit einer Broadcast-Liste können Sie eine Nachricht an viele Empfänger auf einmal senden; die Empfänger können in dieser Liste nicht antworten. Broadcast-Listen sind experimentell und werden sehr wahrscheinlich durch etwas anderes ersetzt werden, bleiben Sie dran :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Ändern Sie Ihre E-Mail-Adresse unter “Einstellungen → Erweitert → Passwort und E-Mail-Konto” und @@ -1594,17 +1479,19 @@ gesendet haben, Nachrichten an Ihre neue Adresse senden.
Allerdings benötigen einige Anbieter besondere Einstellungen, um ordnungsgemäß zu funktionieren; eine von NutzerInnen erstellte Sammlung zu einigen Optionen findet sich unter Provider Overview.Autocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -974,7 +906,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1039,10 +969,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -If you don’t need a longer-lived copy of your messages on the server, -you can also turn on “delete messages from server automatically”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1760,19 +1626,19 @@ However, some providers need special options to work properly, see Provider Overview
Delta Chat is a reliable, decentralized and secure messaging app, -available for mobile and desktop platforms.
+Delta Chat es una aplicación de mensajería segura, descentralizada y confiable. Está disponible para las plataformas móviles y del escritorio.
-Delta Chat feels like Whatsapp or Telegram but you can also use and regard it as an e-mail app. -You can signup anonymously to a variety of interoperable chatmail servers -which are minimal e-mail servers optimized for fast and secure operations. -Or you may use classic e-mail servers and an existing e-mail account -in which case Delta Chat acts as an e-mail app.
+Delta Chat parece como Whatsapp o Telegram, pero también puedes utilizarlo y considerarlo como una aplicación de correo electrónico. +Puedes registrarte de forma anónima en varios servidores de chatmail interoperables +que son servidores de correo electrónico mínimos y optimizados para operaciones rápidas y seguras. +O puedes utilizar servidores de correo electrónico clásicos y una cuenta de correo electrónico existente +en cuyo caso, Delta Chat actúa como una aplicación de correo electrónico.
To securely setup contact with others scan an invite QR code -or share an invite link. -This is required when using a (default) chatmail-based chat profile -because chatmail servers reject un-encrypted outgoing messages.
+Para establecer contacto con otros de forma segura escanea un código QR de invitación +o comparte un enlace de invitación. +Esto es necesario cuando se utiliza un perfil de chat (predeterminado) basado en chatmail +porque los servidores de chatmail rechazan los mensajes salientes no cifrados.
-If you create a chat profile with a classic e-mail address -you may manually create a contact if you know their e-mail address -and then write a message to them -even if the recipient is not using Delta Chat.
+Si crees un perfil de chat con una dirección de correo electrónico clásica +puedes crear manualmente un contacto si conoces su dirección de correo electrónico +y escribirle un mensaje +aunque el destinatario no utilice Delta Chat.
Anonymous chat profiles with fast, secure and interoperable chatmail servers -which offer instant Push Notifications for iOS and Android devices.
-Pervasive multi-profile and multi-device support on all platforms.
-Interactive web apps in chats for gaming and collaboration
-Audited end-to-end encryption -safe against network and server attacks.
-Free and Open Source software, both app and server side. -Built on E-mail and Web Internet Standards, -to avoid “yet another standard syndrome (xkcd 927)”
-Soporte omnipresente, múltiples perfiles y múltiples dispositivos en todas las plataformas.
+ +Interactivas aplicaciones de web en un chat para jugar y colaborar
+ +Cifrado de extremo a extremo auditado +seguro contra ataques a la red y al servidor.
+ +Quizás quieres aprender cómo se usa el mismo perfil en múltiples dispositivos.
Saved Messages is a chat that you can use to easily remember and find messages.
+Mensajes guardados es un chat que puedes utilizar para recordar y encontrar mensajes fácilmente.
In any chat, long tap or right click a message and select Save
+En cualquier chat, mantén pulsado o haz clic con el botón derecho en un mensaje y selecciona Guardar
Saved messages are marked by the symbol
-
-next to the timestamp
Los mensajes guardados se marcan con el símbolo
+
+junto a la marca de tiempo
Later, open the “Saved Messages” chat - and you will see the saved messages there.
-By tapping ,
-you can go back to the original message in the original chat
Después puedes abrir el chat “Mensajes guardados” - y allí verás los mensajes guardados.
+Con pulsar a ,
+puedes volver al mensaje original en el chat original
Finally, you can also use “Save Messages” to take personal notes - open the chat, type something, add a photo or a voice message etc.
@@ -352,9 +344,9 @@ may it be by sender, by device cleanup -You can sometimes see a green dot
-next to the avatar of a contact.
-It means they were recently seen in the last 10 minutes:
A veces puede ver un punto verde
+junto al avatar de un contacto.
+Significa que ha sido visto recientemente en los últimos 10 minutos:
If you have sent a message accidentally, -from the same menu, select Delete and then Delete for Everyone.
+Si has enviado un mensaje accidentalmente +desde el mismo menú, seleccione Borrar y después Borrar para todos.
While edited messages will have the word “Edited” next to the timestamp, -deleted messages will be removed without a marker in the chat. -Notifications are not sent and there is no time limit.
+Mientras que los mensajes editados tendrán la palabra “Editado” junto a la marca de tiempo, +los mensajes borrados serán eliminados sin un marcador en el chat. +No se envían notificaciones y no hay límite de tiempo.
Note, that the original message may still be received by chat members who could have already replied, forwarded, saved, screenshotted or otherwise copied the message.
@@ -723,10 +715,10 @@ that achieves “instant delivery” of messages for all chatmail servers including a potential one you might setup yourself without our permission. Welcome to the power of the interoperable and massive chatmail and e-mail system :) -Autocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Protocolos de Secure-Join
-se utilizan para establecer chats con cifrado de extremo a extremo garantizado
-que protege contra ataques de red y servidores comprometidos.
-Los chats marcados con una estampilla verde
-
-garantizan mensajes cifrados de extremo a extremo.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
Todos los mensajes cifrados de extremo a extremo tienen un candado:
- -El cifrado de extremo a extremo está garantizado si hay una estampilla verde cerca del nombre del chat:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
Si ambos dispositivos están en línea,
-ambas partes eventualmente verán un chat (grupal o directo) con una estampilla verde
-
-junto al título.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
Si uno de los dispositivos está sin conexión, las estampillas verdes solo aparecerán más tarde cuando el dispositivo vuelva a estar conectado a Internet y se complete el protocolo de red Secure-Join.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
¡Felicitaciones!
-Ahora utilizarás automáticamente el cifrado de extremo a extremo garantizado
-con este contacto y ambos pueden agregarse mutuamente a grupos con estampilla verde
-,
-de esta manera se propagará automáticamente el cifrado de extremo a extremo garantizado entre sus miembros.
Congratulations! +You now will automatically use end-to-end encryption +with this contact. +If you add each other to chat groups, +end-to-end encryption will be established among all members.
Títulos de chat con estampillas verdes +
A contact profile might show a green checkmark
-significan que todos los mensajes en el chat estarán cifrados de extremo a extremo
-y no pueden ser leídos o alterados por servidores de correo electrónico o proveedores de Internet comprometidos.
-Unirse a chats grupales con estampillas verdes
-difunde de manera segura la información de cifrado de todos (y las estampillas verdes)
-de una manera que garantiza el cifrado de extremo a extremo en el grupo y entre los miembros.
Perfiles de contacto con estampillas verdes
-
-significa que el envío de mensajes a un contacto está actualmente garantizado que está cifrado de extremo a extremo.
-Cada contacto con estampilla verde hizo un escaneo directo de QR contigo
-o fue presentado por otro contacto con estampilla verde.
-Las presentaciones ocurren automáticamente al agregar miembros a grupos.
-Quien agregue un contacto a un grupo con estampilla verde se convierte en un presentador
-para aquellos miembros que aún no conocían al contacto agregado.
-En un perfil de contacto, puedes tocar repetidamente el texto “Presentado por …”
-hasta llegar al que hizo un escaneo directo de QR contigo.
Ten en cuenta que en un perfil de contacto puedes ver y tocar a las personas que te presentaron a ese contacto, pero puede pasar que no haya una estampilla verde en el título del perfil. Esto generalmente significa que el contacto “envió un mensaje desde otro dispositivo”.
+and an “Introduced by” line. +Every green-checkmarked contact either did a direct QR-scan with you +or was introduced by a another green-checkmarked contact. +Introductions happen automatically when adding members to groups. +Whoever adds a green-checkmarked contact to a group with only green-checkmarked members +becomes an introducer. +In a contact profile you can tap on the “Introduced by …” text repeatedly +until you get to the one with whom you directly did a QR-scan.Para obtener una discusión más detallada sobre “cifrado de extremo a extremo garantizado”, por favor consulta los protocolos Secure-Join y lee específicamente sobre “Grupos Verificados”, el término técnico de lo que aquí se llama chats “marcados con una estampilla verde” o “cifrados de extremo a extremo garantizado”.
-Tu chat con un contacto perdió el cifrado de extremo a extremo garantizado. -La estampilla verde fue eliminada para este chat y contacto cuando veas esta advertencia. -Si encuentras sorprendente la repentina pérdida de cifrado de extremo a extremo garantizado -para este contacto, ¡no aceptes la advertencia! -En su lugar, verifica con tu contacto a través de un segundo canal -como una videollamada, otra app de chat o una llamada telefónica, -para averiguar qué sucedió.
- -Si tu contacto realmente causó la caída del cifrado de extremo a extremo garantizado, por favor vea los siguientes párrafos para conocer las razones comunes y sus mitigaciones. Sin embargo, todos los demás chats marcados con una estampilla verde siguen estando cifrados de extremo a extremo garantizado, incluso si el contacto es miembro allí.
- -Tu contacto está usando Delta Chat en un segundo dispositivo (teléfono o computadora portátil)
- -Si tienen otro dispositivo con la aplicación Delta Chat en funcionamiento, -deben eliminar la cuenta del nuevo dispositivo -y agregarla como un segundo dispositivo según se describe aquí. -Tan pronto como te envíen un mensaje después, la advertencia desaparecerá -y se establecerá el cifrado garantizado con ambos dispositivos de tu contacto.
- -Tu contacto reinstaló Delta Chat utilizando su antiguo inicio de sesión de cuenta
- -Si tienen un archivo de respaldo, -deben eliminar la cuenta del nuevo dispositivo -y en su lugar importar el archivo de respaldo para recrear su cuenta. -Tan pronto como te envíen un mensaje después, la advertencia desaparecerá -y se restablecerá el cifrado garantizado para este contacto.
- -Si no tienen un archivo de respaldo, es mejor realizar un escaneo QR con tu compañero de chat para restablecer el cifrado de extremo a extremo garantizado.
- -Tu contacto envió un correo a través de una interfaz de correo web o otra aplicación de correo electrónico y volverá a usar Delta Chat pronto.
- -Si estás seguro de que el contacto a veces utiliza webmail, -o alguna otra aplicación de correo que carece de cifrado de extremo a extremo, -entonces puedes aceptar la advertencia. -Tan pronto como tu contacto vuelva a utilizar Delta Chat, -el cifrado de extremo a extremo garantizado se restablecerá automáticamente.
- -Tus contactos dejaron de usar Delta Chat completamente
- -A veces, mantenerse en contacto es más importante que el cifrado de extremo a extremo. El cifrado de capa de transporte (“Transport Layer Encryption” o TLS) puede proteger de manera significativa la confidencialidad de tus mensajes entre tu dispositivo y el servidor de correo electrónico. Pero sin el cifrado de extremo a extremo, tú y tu contacto están confiando en que el servidor de correo electrónico no lea ni manipule tus mensajes, y que no los entregue a terceros.
- -En cualquier caso, no puedes hacer mucho más que aceptar la advertencia. -Por favor, también elimina el contacto de cualquier grupo activo con estampilla verde -que puedas encontrar en “Chats compartidos” en el perfil del contacto. -Esto evitará que tu contacto reciba mensajes “ilegibles”.
- -Si el contacto eliminó Delta Chat debido a un comportamiento defectuoso o indeseable, -por favor considera publicar en nuestro foro de soporte -para ayudarnos a identificar y solucionar problemas comunes. ¡Gracias!
-Sí, Delta Chat utiliza un subconjunto seguro de OpenPGP -y solo muestra un indicador de seguridad de candado en un mensaje -si todo el mensaje está correctamente cifrado y firmado. -Por ejemplo, las “firmas desvinculadas” no se consideran seguras.
+Yes, Delta Chat uses a secure subset of OpenPGP +requiring the whole message to be properly encrypted and signed. +For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. Most publicly discussed OpenPGP security problems @@ -955,7 +895,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1020,8 +958,6 @@ If the involved e-mail servers support mantener un cifrado de extremo a extremo garantizado sobre el cifrado TLS proporciona seguridad generalizada entre tus dispositivos y los del destinatario. Ni siquiera tu proveedor de correo electrónico o de Internet podrá leer o modificar tus mensajes.
Delta Chat protege la mayoría de los metadatos de los mensajes al colocar la siguiente información en la parte cifrada de extremo a extremo de los mensajes:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+Los servidores de correo electrónico no obtienen acceso a estos metadatos protegidos -pero sí ven la fecha del mensaje así como el tamaño del mensaje, -y, lo que es más importante, las direcciones del remitente y del destinatario. -Los servidores de correo electrónico necesitan direcciones de destinatarios para enrutar y -entregar mensajes a los dispositivos del destinatario.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -Puede verificar manualmente el estado de cifrado de extremo a extremo en el diálogo “Cifrado” (perfil de usuario en Android/iOS o hacer clic derecho en el elemento de lista de chat de un usuario en el escritorio). Delta Chat muestra dos huellas digitales allí. Si las mismas huellas digitales aparecen en su propio dispositivo y en el dispositivo de su contacto, la conexión es segura.
- -No, not yet.
-Un pequeño candado en una burbuja de mensaje indica que el mensaje fue correctamente cifrado de extremo a extremo por el remitente dado. Si no hay candado, es probable que el mensaje no esté correctamente cifrado de extremo a extremo, ya que el remitente utiliza una aplicación o interfaz de correo web sin soporte para el cifrado de extremo a extremo.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -Si necesitas un chat cifrado de extremo a extremo de forma segura con un contacto que está utilizando su cuenta tanto con Delta Chat como con aplicaciones no-Autocrypt (por ejemplo, webmail), lo mejor es configurar cifrado de extremo a extremo garantizado con ellos y luego crear un grupo cifrado de extremo a extremo garantizado con ustedes dos como miembros. En este chat de grupo, todos los mensajes estarán cifrados de extremo a extremo, incluso si el chat directo entre ustedes dos tiene una advertencia de “… envió un mensaje desde otro dispositivo”.
- -La mejor manera de asegurar que cada mensaje esté cifrado de extremo a extremo -y que los metadatos se borren lo más rápido posible -es utilizando chats con cifrado de extremo a extremo garantizado -y activando la desaparición de mensajes.
- -Los chats con cifrado de extremo a extremo garantizado protegen contra ataques MITM -y al activar “mensajes efímeros” se borran los mensajes -en el servidor después de un tiempo configurado por el usuario.
- -Si no necesitas una copia de tus mensajes en el servidor durante más tiempo, -también puedes activar “eliminar mensajes del servidor automáticamente”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat no soporta Perfect Forward Secrecy (PFS). -Esto significa que si se filtra tu clave privada de descifrado de Delta Chat, -y alguien ha recopilado tus mensajes previos en tránsito, -podrán descifrarlos y leerlos utilizando la clave de descifrado filtrada.
+No, not yet.
-Ten en cuenta, sin embargo, que si alguien obtiene tus claves de descifrado, -también podrán obtener tus mensajes, -independientemente de si se implementa o no el Perfect Forward Secrecy. -La situación típica en el mundo real para las claves de descifrado filtradas es la incautación del dispositivo, -que discutimos en nuestra respuesta sobre metadatos e incautación de dispositivos.
+Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, +and someone has collected your prior in-transit messages, +they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages.
-It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +Puede verificar manualmente el estado de cifrado de extremo a extremo en el diálogo “Cifrado” (perfil de usuario en Android/iOS o hacer clic derecho en el elemento de lista de chat de un usuario en el escritorio). Delta Chat muestra dos huellas digitales allí. Si las mismas huellas digitales aparecen en su propio dispositivo y en el dispositivo de su contacto, la conexión es segura.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1717,19 +1604,19 @@ Esto es lo que hace Delta Chat con esos permisos:
Sin embargo, algunos proveedores necesitan opciones especiales para funcionar correctamente, ver Descripción de proveedoresAutocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -948,7 +880,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1013,10 +943,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -If you don’t need a longer-lived copy of your messages on the server, -you can also turn on “delete messages from server automatically”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1693,17 +1566,19 @@ Voici ce que fait Delta Chat avec ces autorisations:
Cependant, il faut activer des options spéciales pour que cela fonctionne correctement avec certains fournisseurs… Voir la liste des fournisseurs.Autocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -974,7 +906,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1039,10 +969,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -If you don’t need a longer-lived copy of your messages on the server, -you can also turn on “delete messages from server automatically”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1760,19 +1626,19 @@ However, some providers need special options to work properly, see Provider Overview
Autocrypt viene utilizzato automaticamente per stabilire la crittografia end-to-end con contatti e chat di gruppo. Autocrypt utilizza un sottoinsieme limitato e sicuro dello standard OpenPGP. I messaggi crittografati end-to-end sono contrassegnati da un lucchetto
-.
Delta Chat utilizza un sottoinsieme sicuro dello standard OpenPGP +per fornire la crittografia end-to-end automatica utilizzando questi protocolli:
-Protocolli Secure-Join
-vengono utilizzati per stabilire chat con crittografia end-to-end garantita
-che protegge dagli attacchi di rete e dai server compromessi.
-Chat contrassegnata da un segno di spunta verde
-
-garantisce messaggi crittografati end-to-end.
Secure-Join +per scambiare informazioni sulla configurazione della crittografia tramite la scansione del codice QR o i “link di invito”.
+Autocrypt viene utilizzato per stabilire +automaticamente la crittografia end-to-end tra i contatti e tutti i membri di una chat di gruppo.
+Condivisione di un contatto con una +chat +consente ai destinatari di utilizzare la crittografia end-to-end con il contatto.
+Delta Chat non esegue query, pubblica o interagisce con alcun server di chiavi OpenPGP.
Tutti i messaggi crittografati end-to-end portano un lucchetto:
- -La crittografia end-to-end è garantita se è presente un segno di spunta verde accanto al titolo della chat:
- -Tutti i messaggi in Delta Chat sono crittografati end-to-end per impostazione predefinita. +Dalla serie di rilasci della Versione 2 di Delta Chat (Luglio 2025) +non ci sono più lucchetti o marcatori simili, sui messaggi crittografati end-to-end.
-Se disponi di un secondo canale di comunicazione con il tuo partner di chat, -come una chat video o un altro messenger, -puoi generare un link d’invito.
+Se si utilizzano i relays di chatmail, +è impossibile ricevere o inviare messaggi senza la crittografia end-to-end.
-Se siete insieme di persona, -puoi mostrare un codice QR al tuo partner di chat.
+Se invece si crea un profilo utilizzando un server di posta elettronica classico,
+è possibile inviare e ricevere messaggi senza crittografia end-to-end.
+I messaggi privi di crittografia end-to-end sono contrassegnati da un’icona e-mail
+.
È possibile inviare un link di invito attraverso un’altra chat privata, +mostrare un codice QR di invito quando si è vicini o in una videochiamata, +o fare clic su un “contatto” condiviso in una chat.
Per inviti diretti alla chat 1:1,
-tocca l’icona del codice QR
+
Per inviti diretti alla chat 1:1,
+toccare l’icona del Codice QR
nella schermata principale dell’app Delta Chat.
Lascia che il tuo partner di chat esegua la scansione dell’immagine QR -con la loro app Delta Chat, -oppure fai clic su “Copia” o “Condividi” per creare un collegamento di invito -e condividilo con il tuo partner di chat.
+Chiedere al partner di chat di scansionare l’immagine QR +con la propria app Delta Chat, +oppure cliccare su “Copia” o “Condividi” per creare un link di invito +e condividerlo con il partner di chat.
-Ora attendi che i messaggi di rete Secure-Join vengano scambiati tra entrambi i dispositivi.
+Ora aspettate che la crittografia end-to-end venga stabilita.
Se entrambi i dispositivi sono online,
-entrambe le parti vedranno eventualmente una chat (di gruppo o diretta) con un segno di spunta verde
-
-accanto al titolo.
Se entrambe le parti sono online, vedranno presto una chat (di gruppo o diretta) +e potranno iniziare a messaggiare in modo sicuro.
Se uno dei dispositivi è offline, verranno visualizzati solo i segni di spunta verdi -verranno visualizzati in seguito quando il dispositivo sarà nuovamente connesso a Internet -e il protocollo di rete Secure-Join è stato completato.
+Se una delle due parti è offline o con rete scadente, +la possibilità di chattare viene ritardata fino al ripristino della connettività.
Congratulazioni!
-Ora utilizzerai automaticamente la crittografia end-to-end garantita
-con questo contatto potete aggiungervi a vicenda nei gruppi contrassegnati da un segno di spunta verde
-,
-diffondendo così automaticamente la crittografia end-to-end garantita tra i suoi membri.
Congratulazioni! +Ora utilizzerai automaticamente la crittografia end-to-end +con questo contatto. +Se vi aggiungete a gruppi di chat, +la crittografia end-to-end sarà stabilita tra tutti i membri.
Titoli di chat con segni di spunta verde +
Il profilo di un contatto potrebbe mostrare una spunta verde
-significa che tutti i messaggi nella chat saranno crittografati end-to-end
-e non possono essere letti o modificati da server di e-mail o provider Internet compromessi.
-Partecipare alle chat di gruppo contrassegnate da un segno di spunta verde diffonde in modo sicuro le informazioni di crittografia di tutti (e i segni di spunta verdi)
-in modo da garantire la crittografia end-to-end nel gruppo e tra i membri.
Profili di contatto con segni di spunta verdi
-
-significa che attualmente è garantita la crittografia end-to-end dei messaggi a un contatto.
-Ogni contatto contrassegnato dal segno di spunta verde ha effettuato una scansione QR diretta con te
-o è stato presentato da un altro contatto contrassegnato da un segno di spunta verde.
-Le presentazioni avvengono automaticamente quando si aggiungono membri ai gruppi.
-Chi aggiunge un contatto a un gruppo contrassegnato da un segno di spunta verde diventa un introduttore
-a quei membri che non erano ancora a conoscenza del contatto aggiunto. In un profilo di contatto è possibile toccare ripetutamente il testo “Presentato da…”.
-fino ad arrivare a quello con cui hai effettuato direttamente una scansione QR.
Tieni presente che nel profilo di un contatto potresti vedere e toccare gli introduttori -ma non c’è il segno di spunta verde nel titolo del profilo. -Questo di solito significa che il contatto “ha inviato un messaggio da un altro dispositivo”.
+e una linea “Verificato da”. +Ogni contatto con la spunta verde ha fatto un QR-scan con te +o è stato verificato da un altro contatto con la spunta verde. +La verifica si ha automaticamente all’aggiunta dei membri nei gruppi. +Chiunque aggiunga un contatto con spunta verde a un gruppo con solo membri con la spunta verde +diventa colui che l’ha verificato. +Nel profilo di un contatto puoi premere sul campo “Verificato da …” ripetutamente +fino a che vedi con chi hai avuto un QR-scan.Per una discussione più approfondita sulla “crittografia end-to-end garantita” consultare Protocolli Secure-Join e leggi nello specifico i “Gruppi Verificati”, il termine tecnico di quelle che qui vengono chiamate chat “con segno di spunta verde” o “crittografate end-to-end garantite”.
-La tua chat con un contatto che ha perso la crittografia end-to-end garantita. -Il segno di spunta verde è stato rimosso per questa chat e per questo contatto quando vedi questo avviso. -Se riscontri l’improvvisa rimozione della crittografia end-to-end garantita -inaspettatamente per questo contatto allora non accettare l’avviso! -Verifica invece con il tuo contatto attraverso un secondo canale -come una videochiamata, un altro messenger o una telefonata, -per scoprire cosa è successo.
- -Se il tuo contatto ha effettivamente causato la rimozione della crittografia end-to-end garantita -consultare i paragrafi successivi per i motivi comuni e le relative attenuazioni. -Indipendentemente da ciò, tutte le altre chat contrassegnate da un segno di spunta verde rimangono garantite con crittografia end-to-end -anche se il contatto è un membro.
- -Il tuo contatto sta utilizzando Delta Chat su un secondo dispositivo (telefono o laptop)
- -Se hanno un altro dispositivo con l’app Delta Chat in esecuzione, -dovrebbero rimuovere il profilo dal nuovo dispositivo -e aggiungerlo come secondo dispositivo come descritto qui. -Non appena ti invieranno un messaggio, l’avviso scomparirà -e la crittografia garantita viene stabilita con entrambi i dispositivi del tuo contatto.
- -Il tuo contatto ha reinstallato Delta Chat utilizzando il vecchio login del profilo
- -Se hanno un file di backup, -dovrebbero rimuovere il profilo dal nuovo dispositivo -e piuttosto importare il file di backup per ricreare il proprio profilo. -Non appena ti invieranno un messaggio, l’avviso scomparirà -e la crittografia garantita viene ristabilita per questo contatto.
- -Se non hanno un file di backup, è meglio eseguire una scansione QR -con il tuo partner di chat per ristabilire la crittografia end-to-end garantita.
- -Il tuo contatto ha inviato un’e-mail tramite un’interfaccia webmail o un’altra app di posta elettronica -e presto tornerà a utilizzare Delta Chat.
- -Se sei sicuro che il contatto a volte utilizza la webmail, -o un’altra app di posta priva di crittografia end-to-end, -allora puoi accettare l’avvertimento. -Non appena il tuo contatto utilizzerà nuovamente Delta Chat, -la crittografia end-to-end garantita verrà ristabilita automaticamente.
- -Il tuo contatto ha smesso completamente di utilizzare Delta Chat
- -A volte rimanere in contatto è più importante della crittografia end-to-end. -“Transport Layer Encryption” (TLS) può comunque proteggere in modo significativo -la riservatezza dei tuoi messaggi tra il tuo dispositivo e il server di posta elettronica. -Ma senza la crittografia end-to-end tu e il tuo contratto vi fidate del vostro server di posta elettronica -a non leggere o manipolare i tuoi messaggi e a non trasmetterli a terzi.
- -In ogni caso, non puoi fare molto altro che accettare l’avvertimento. -Rimuovi anche il contatto da qualsiasi gruppo attivo contrassegnato da un segno di spunta verde -che puoi trovare in “Chat condivise” nel profilo dei contatti. -Ciò evita che il tuo contatto riceva messaggi “illeggibili”.
- -Se il contatto ha rimosso Delta Chat a causa di bug o di comportamenti indesiderati, -ti invitiamo a pubblicare post sul nostro forum di supporto -per aiutarci a identificare e affrontare i problemi comuni. Grazie!
-Sì, Delta Chat utilizza un sottoinsieme sicuro di OpenPGP -e visualizza solo un indicatore di sicurezza lucchetto su un messaggio -se l’intero messaggio è crittografato e firmato correttamente. -Ad esempio, le “Firme distaccate” non sono considerate sicure.
+che richiede che l’intero messaggio sia correttamente crittografato e firmato. +Ad esempio, le “Firme staccate” non sono considerate sicure.OpenPGP non è insicuro di per sé. La maggior parte dei problemi di sicurezza di OpenPGP discussi pubblicamentederivano in realtà da una cattiva usabilità o da cattive implementazioni di strumenti o app (o entrambi). @@ -957,10 +894,10 @@ e verificato per la sicurezza nel 2019 e nel 2024 per migliorare ulteriormente le caratteristiche di sicurezza implementando il nuovo aggiornamento crittografico IETF OpenPGP che per fortuna è stato adottato nell’estate 2023.
-Anche se non è garantito che i tuoi messaggi siano crittografati end-to-end, -sono ancora protetti dai fornitori di Internet come le società di telefonia mobile o via cavo. -Tuttavia, i provider di posta elettronica tuoi e del destinatario -potranno leggere, analizzare o addirittura modificare i tuoi messaggi, -compresi eventuali allegati, -se non sono crittografati end-to-end.
+Se inviate o ricevete messaggi e-mail senza crittografia end-to-end (utilizzando un server e-mail classico), +sono comunque protetti dalle compagnie telefoniche o via cavo che non possono leggere o modificare i vostri messaggi e-mail. +Ma sia il vostro provider e-mail che quello del destinatario +possono leggere, analizzare o modificare i vostri messaggi, compresi gli allegati.
Delta Chat per impostazione predefinita utilizza Crittografia TLS rigorosa @@ -1025,10 +960,6 @@ Se i server e-mail coinvolti supportano mantenere la crittografia end-to-end garantita oltre alla crittografia TLS -fornisce una sicurezza pervasiva tra i tuoi dispositivi e quelli del destinatario. -Nemmeno il tuo provider e-mail o Internet sarà in grado di leggere o modificare i tuoi messaggi.
Delta Chat protegge la maggior parte dei metadati dei messaggi inserendo le seguenti informazioni -nella parte crittografata end-to-end dei messaggi:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
the message date,
+sender and receiver addresses
+and message size.
+I server E-Mail non hanno accesso a questi metadati protetti -ma vedono la data del messaggio e la dimensione del messaggio, -e, cosa ancora più importante, gli indirizzi del mittente e del destinatario. -I server E-Mail necessitano di indirizzi di destinatari per instradare e -consegnare messaggi ai dispositivi del destinatario.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Entrambi per la protezione dai server e-mail che raccolgono metadati -nonché contro il pericolo di sequestro del dispositivo -consigliamo di utilizzare un’istanza del server e-mail ottimizzata per Delta Chat -per creare profili temporanei pseudonimi tramite scansioni di codici QR. -Tieni presente che le app Delta Chat su tutte le piattaforme supportano più profili -in questo modo puoi utilizzare facilmente profili “1 settimana” o “1 mese” specifici per azioni accanto al tuo profilo “principale”. -con la consapevolezza che tutti i dati temporanei del profilo, insieme a tutti i metadati, verranno cancellati. -Inoltre, se un dispositivo viene sequestrato, i contatti utilizzano profili e-mail temporanei -non possono essere identificati facilmente, rispetto ai messaggeri che rivelano -numeri di telefono nei gruppi di chat che a loro volta sono spesso associati a identità legali.
+Both for protecting against metadata-collecting e-mail servers +as well as against the threat of device seizure +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. +Note that Delta Chat apps on all platforms support multiple profiles +so you can easily use situation-specific profiles next to your “main” profile +with the knowledge that all their data, along with all metadata, will be deleted. +Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily.
-È possibile verificare manualmente lo stato della crittografia end-to-end nella finestra di dialogo “Crittografia”. -(profilo utente su Android/iOS o clic con il pulsante destro del mouse sull’elemento dell’elenco chat di un utente sul desktop). -Delta Chat mostra due impronte digitali. -Se sul tuo dispositivo e su quello del tuo contatto vengono visualizzate le stesse impronte digitali, -la connessione è sicura.
- -No, non ancora.
-Un piccolo lucchetto in un fumetto denota -che il messaggio è stato correttamente crittografato end-to-end dal mittente specificato. -Se non è presente alcun lucchetto, il messaggio non è stato crittografato correttamente end-to-end -molto probabilmente perché il mittente utilizza un’app o un’interfaccia webmail -senza supporto per la crittografia end-to-end.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-Se un contatto utilizza un’app e-mail non Autocrypt, -tutti i messaggi che coinvolgono questo contatto (in un gruppo o in una chat 1:1) -non sarà crittografato end-to-end e quindi non mostrerà un “lucchetto” con i messaggi. -Tieni presente che anche se i tuoi contatti utilizzano Delta Chat sul proprio profilo, -potrebbero anche utilizzare un’app di posta elettronica non Autocrypt su quel profilo -che quindi potrebbe causare messaggi non crittografati in modo intermittente. -La risposta non crittografata a messaggi non crittografati è richiesta da Autocrypt -per evitare messaggi illeggibili tra i tuoi contatti -e la loro app e-mail non Autocrypt.
- -Se hai bisogno di una chat crittografata end-to-end sicura con un contatto -chi utilizza il proprio profilo sia con Delta Chat che con app non Autocrypt (ad esempio webmail), -è meglio configurare la crittografia end-to-end garantita con loro -e quindi crea una chat di gruppo crittografata end-to-end garantita con voi due come membri. -In questa chat di gruppo tutti i messaggi verranno crittografati end-to-end -anche se la chat diretta tra voi due ha a -“… inviato un messaggio da un altro dispositivo” avviso.
- -Il modo migliore per garantire che ogni messaggio sia crittografato end-to-end, -e i metadati vengono eliminati il più rapidamente possibile -è utilizzare chat con crittografia end-to-end garantita -e l’attivazione dei messaggi a scomparsa.
- -Le chat crittografate end-to-end garantiscono la protezione dagli attacchi MITM -e l’attivazione dei “messaggi che scompaiono” elimina i messaggi -sul server dopo un tempo configurato dall’utente.
- -Se non hai bisogno di una copia più longeva dei tuoi messaggi sul server, -puoi anche attivare “elimina messaggi dal server”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat non supporta Perfect Forward Secrecy (PFS). -Ciò significa che se la tua chiave di cifratura privata Delta Chat viene divulgata, -e qualcuno ha raccolto i tuoi precedenti messaggi in transito, -sarà in grado di decifrarli e leggerli utilizzando la chiave di cifratura trapelata.
+No, non ancora.
-Tieni presente, tuttavia, che se qualcuno ottiene le tue chiavi di decrittazione, -in genere saranno anche in grado di ricevere i tuoi messaggi, -indipendentemente dal fatto che Perfect Forward Secrecy sia attivo o meno. -La tipica situazione reale in caso di fuga di chiavi di decrittazione è il sequestro del dispositivo -di cui discutiamo nella nostra risposta sui metadati e sul sequestro dei dispositivi.
+Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, +and someone has collected your prior in-transit messages, +they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages.
-È possibile che Delta Chat si evolva per supportare Perfect Forward Secrecy, -perché OpenPGP è solo un contenitore per messaggi crittografati -ma la gestione delle chiavi di crittografia (e quindi la rotazione delle chiavi o “cricchetto”) -potrebbero essere organizzati in modo flessibile. -Vedi prototipo PFS di Seqouia -per gli esperimenti esistenti nella comunità degli implementatori di OpenPGP.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-Dipende da cosa è importante per te. -Delta Chat non supporta PFS come fa Signal -ma fornisce chat crittografate end-to-end garantite -che sono sicuri contro server compromessi o reti danneggiate. -Signal e la maggior parte degli altri servizi di messaggistica che supportano PFS non forniscono -uno schema pratico per proteggere i gruppi di chat dagli attacchi di rete -che sono probabilmente più preoccupanti -di un potenziale utente malintenzionato che si impadronisce del tuo telefono e della configurazione di crittografia privata -ma in qualche modo non i tuoi messaggi, ma ha un registro completo di tutti -messaggi crittografati precedenti.
+No, non ancora.
-In ogni caso, la crittografia end-to-end di Delta Chat utilizza un sottoinsieme sicuro di OpenPGP -che è stato controllato in modo indipendente sulla sicurezza.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +È possibile verificare manualmente lo stato della crittografia end-to-end nella finestra di dialogo “Crittografia”. +(profilo utente su Android/iOS o clic con il pulsante destro del mouse sull’elemento dell’elenco chat di un utente sul desktop). +Delta Chat mostra due impronte digitali. +Se sul tuo dispositivo e su quello del tuo contatto vengono visualizzate le stesse impronte digitali, +la connessione è sicura.
Con le Liste Trasmissioni puoi inviare un messaggio a più indirizzi contemporaneamente; +i destinatari non possono rispondere in quella chat. +Le Liste Trasmissioni sono ancora altamente sperimentali +e saranno molto probabilmente rimpiazzate con qualcos’altro, restate sintonizzati :)
Nota: +La modifica degli indirizzi e-mail è temporaneamente disabilitata +a causa delle modifiche in corso al nucleo di DeltaChat. +Dovrebbe essere nuovamente disponibile tra qualche mese.
+Cambia il tuo indirizzo in “Impostazioni → Avanzate → Password e Profilo” e @@ -1722,19 +1596,19 @@ Tuttavia, alcuni provider necessitano di opzioni speciali per funzionare corrett vedi Panoramica fornitore
Autocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -967,7 +899,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1032,10 +962,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -If you don’t need a longer-lived copy of your messages on the server, -you can also turn on “delete messages from server automatically”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1751,19 +1617,19 @@ Delta Chat doet het volgende met deze rechten:
Sommige providers verwachten echter bepaalde opties. Bekijk hiervoor het provideroverzichtPamiętaj, że Delta Chat posiada mały i chroniący prywatność system powiadomień push, który zapewnia „natychmiastowe dostarczanie” wiadomości ze wszystkich serwerów chatmail, w tym potencjalnego, który możesz skonfigurować samodzielnie bez naszej zgody. Witamy w potędze interoperacyjnego i ogromnego systemu chatmail i e-mail :)
-Autocrypt służy do automatycznego ustanawiania szyfrowania end-to-end kontaktów i czatów grupowych. Autocrypt wykorzystuje ograniczony i bezpieczny podzbiór standardu OpenPGP. W pełni zaszyfrowane wiadomości są oznaczone kłódką .
Delta Chat wykorzystuje bezpieczny podzbiór standardu OpenPGP do automatycznego szyfrowania typu end-to-end za pomocą następujących protokołów:
-Protokoły Secure-Join służą do nawiązywania rozmów z gwarantowanym szyfrowaniem typu end-to-end, które chroni przed atakami sieciowymi i zagrożonymi serwerami. Czaty oznaczone zielonym znacznikiem wyboru gwarantują szyfrowanie end-to-end wiadomości.
Secure-Join do wymiany informacji o konfiguracji szyfrowania poprzez skanowanie kodów QR lub „linki zaproszeń”.
+Autocrypt służy do automatycznego ustanawiania szyfrowania typu end-to-end między kontaktami a wszystkimi członkami czatu grupowego.
+Udostępnienie kontaktu na czacie umożliwia odbiorcom korzystanie z szyfrowania typu end-to-end z tym kontaktem.
+Delta Chat nie wysyła zapytań, nie publikuje ani nie wchodzi w interakcję z żadnymi serwerami kluczy OpenPGP.
Wszystkie całkowicie zaszyfrowane wiadomości są oznaczone kłódką:
- -Pełne szyfrowanie jest gwarantowane, jeśli obok tytułu czatu znajduje się zielony znacznik wyboru:
- -Wszystkie wiadomości w Delta Chat są domyślnie szyfrowane metodą end-to-end. Od wydania Delta Chat w wersji 2 (lipiec 2025 r.) nie ma już blokad ani podobnych znaczników na wiadomościach szyfrowanych metodą end-to-end.
-Jeśli masz drugi kanał komunikacji ze swoim partnerem na czacie, np. czat wideo lub inny komunikator, możesz wygenerować link zaproszenia.
+Jeśli korzystasz z domyślnych przekaźników chatmail, odbieranie ani wysyłanie wiadomości bez szyfrowania end-to-end jest niemożliwe.
-Jeśli jesteście razem osobiście, możesz pokazać kod QR swojemu rozmówcy.
+Jeśli zamiast tego utworzysz profil przy użyciu klasycznego serwera poczty e-mail, możesz wysyłać i odbierać wiadomości bez szyfrowania end-to-end. Takie wiadomości bez szyfrowania end-to-end są oznaczone ikoną e-mail .
Możesz wysłać link z zaproszeniem za pośrednictwem innego prywatnego czatu, wyświetlić kod QR zaproszenia, gdy kontakty znajdują się obok siebie lub w rozmowie wideo, albo dotknąć „kontakt”, który został udostępniony na czacie.
W przypadku zaproszeń grupowych dotknij tytułu czatu grupy, aby wyświetlić listę jej członków, i wybierz „Kod QR zaproszenia”.
Aby uzyskać bezpośrednie zaproszenia na czat 1:1, dotknij ikony kodu QR na ekranie głównym aplikacji Delta Chat.
Aby wysłać zaproszenie do czatu 1:1, dotknij ikony kodu QR na ekranie głównym aplikacji Delta Chat.
Pozwól swojemu partnerowi czatu zeskanować obraz QR za pomocą aplikacji Delta Chat lub dotknij „Kopiuj” lub „Udostępnij”, aby utworzyć link zaproszenia i udostępnić go swojemu partnerowi czatu.
+Poproś rozmówcę o zeskanowanie obrazu QR za pomocą aplikacji Delta Chat lub dotknij „Kopiuj” lub „Udostępnij”, aby utworzyć link zaproszenia i udostępnić go rozmówcy.
-Teraz poczekaj, aż między obydwoma urządzeniami nastąpi wymiana wiadomości sieciowych Secure-Join.
+Poczekaj, aż szyfrowanie typu end-to-end zostanie nawiązane.
Jeśli oba urządzenia są w trybie online, obie strony ostatecznie zobaczą czat (grupowy lub bezpośredni) z zielonym znacznikiem wyboru obok tytułu.
Jeśli obie strony są online, wkrótce zobaczą czat (grupowy lub bezpośredni) i będą mogły bezpiecznie wysyłać wiadomości.
Jeśli jedno z urządzeń jest w trybie offline, zielone znaczniki wyboru pojawią się później, dopiero gdy urządzenie zostanie ponownie połączone z Internetem i zostanie zrealizowany protokół sieciowy Secure-Join.
+Jeśli jedna ze stron jest offline lub ma słaby zasięg, możliwość czatowania zostanie wstrzymana do czasu przywrócenia połączenia.
Gratulacje! Teraz będziecie automatycznie korzystać z gwarantowanego kompleksowego szyfrowania tego kontaktu i oboje będziecie mogli dodawać się nawzajem do grup oznaczonych zielonym znacznikiem wyboru , w ten sposób automatycznie rozpowszechniając gwarantowane kompleksowe szyfrowanie wśród swoich członków.
Gratulacje! Teraz będziesz automatycznie korzystać z szyfrowania typu end-to-end dla tego kontaktu. Jeśli dodacie się nawzajem do czatów grupowych, szyfrowanie typu end-to-end zostanie nawiązane między wszystkimi członkami.
Tytuły czatów z zielonymi znacznikami wyboru oznaczają, że wszystkie wiadomości na czacie będą w pełni szyfrowane i nie będą mogły zostać odczytane ani zmodyfikowane przez zhakowane serwery poczty e-mail lub dostawców Internetu. Dołączanie do czatów grupowych oznaczonych zielonym znacznikiem bezpiecznie rozpowszechnia informacje o szyfrowaniu wszystkich osób (i zielone znaczniki wyboru) w sposób gwarantujący kompleksowe szyfrowanie w grupie i pomiędzy członkami.
Profile kontaktów z zielonymi znacznikami wyboru oznaczają, że obecnie gwarantujemy, że wiadomości kontaktu będą szyfrowane metodą end-to-end. Każdy kontakt oznaczony zielonym znacznikiem albo wykonał z tobą bezpośrednie skanowanie QR, albo został zweryfikowany przez inny kontakt oznaczony zielonym znacznikiem. Weryfikacje odbywają się automatycznie podczas dodawania członków do grup. Ktokolwiek doda kontakt do grupy oznaczonej zielonym znacznikiem, staje się osobą weryfikującą dla tych członków, którzy jeszcze nie wiedzieli o dodanym kontakcie. W profilu kontaktu możesz wielokrotnie dotykać tekstu „Zweryfikowano przez…”, aż dojdziesz do osoby, z którą bezpośrednio wykonałeś skanowanie QR.
Pamiętaj, że w profilu kontaktu możesz widzieć i klikać osoby weryfikujące, ale w tytule profilu nie ma zielonego znacznika wyboru. Zwykle oznacza to, że kontakt „wysłał wiadomość z innego urządzenia”.
+Profil kontaktu może wyświetlać zielony znacznik wyboru i wiersz „Zweryfikowano przez…”. Każdy kontakt oznaczony zielonym znacznikiem albo wykonał z tobą bezpośrednie skanowanie QR, albo został zweryfikowany przez inny kontakt oznaczony zielonym znacznikiem. Weryfikacje odbywają się automatycznie podczas dodawania członków do grup. Osoba, która doda kontakt oznaczony zielonym znacznikiem wyboru do grupy zawierającej wyłącznie członków oznaczonych zielonym znacznikiem wyboru, staje się osobą weryfikującą. W profilu kontaktu możesz wielokrotnie dotykać tekstu „Zweryfikowano przez…”, aż dojdziesz do osoby, z którą bezpośrednio wykonałeś skanowanie QR.
Aby uzyskać bardziej szczegółowe omówienie „gwarantowanego szyfrowania typu end-to-end”, zobacz Protokoły Secure-Join, a w szczególności przeczytaj o „zweryfikowanych grupach”, technicznym określeniu tak zwanego tutaj „zielonego znacznika wyboru” lub „gwarantowanego szyfrowania end-to-end” czatów.
-Twój czat z kontaktem utracił gwarantowane szyfrowanie typu end-to-end. Gdy zobaczysz to ostrzeżenie, zielony znacznik wyboru dla tego czatu i kontaktu został usunięty. Jeśli zdziwi cię nagły spadek gwarantowanego szyfrowania end-to-end tego kontaktu, nie akceptuj ostrzeżenia! Zamiast tego skontaktuj się ze swoim kontaktem za pośrednictwem drugiego kanału, takiego jak rozmowa wideo, inny komunikator lub rozmowa telefoniczna, aby dowiedzieć się, co się stało.
- -Jeśli twój kontakt rzeczywiście spowodował spadek gwarantowanego szyfrowania typu end-to-end, zapoznaj się z kolejnymi akapitami, aby poznać typowe przyczyny i sposoby ich łagodzenia. Niezależnie od tego, wszystkie inne czaty oznaczone zielonym znacznikiem są w pełni szyfrowane, nawet jeśli kontakt jest ich członkiem.
- -Twój kontakt korzysta z Delta Chat na drugim urządzeniu (telefonie lub laptopie)
- -Jeśli ma inne urządzenie z uruchomioną aplikacją Delta Chat, powinien usunąć konto z nowego urządzenia i dodać je jako drugie urządzenie zgodnie z opisem tutaj. Gdy tylko skontaktuje się z tobą później, ostrzeżenie zniknie, a na obu urządzeniach twojego kontaktu zostanie ustanowione gwarantowane szyfrowanie.
- -Twój kontakt ponownie zainstalował Delta Chat, używając swojego starego loginu do konta
- -Jeśli ma plik kopii zapasowej, powinien usunąć konto z nowego urządzenia i zamiast tego zaimportować plik kopii zapasowej, aby ponownie utworzyć konto. Gdy tylko skontaktuje się z tobą później, ostrzeżenie zniknie, a dla tego kontaktu zostanie przywrócone gwarantowane szyfrowanie.
- -Jeśli nie ma pliku kopii zapasowej, najlepiej wykonać skanowanie QR ze swoim partnerem czatu, aby przywrócić gwarantowane szyfrowanie end-to-end.
- -Twój kontakt wysłał wiadomość e-mail za pośrednictwem interfejsu poczty internetowej lub innej aplikacji e-mail i wkrótce ponownie zacznie korzystać z Delta Chat.
- -Jeśli masz pewność, że kontakt czasami korzysta z poczty internetowej lub innej aplikacji pocztowej, która nie zapewnia szyfrowania end-to-end, możesz zaakceptować ostrzeżenie. Gdy tylko twój kontakt ponownie skorzysta z Delta Chat, gwarantowane szyfrowanie end-to-end zostanie automatycznie przywrócone.
- -Twój kontakt całkowicie przestał korzystać z Delta Chat
- -Czasami utrzymanie kontaktu jest ważniejsze niż szyfrowanie end-to-end. „Szyfrowanie warstwy transportowej” (TLS) może w dalszym ciągu w znaczący sposób chronić poufność wiadomości przesyłanych między urządzeniem a serwerem poczty e-mail. Jednak bez kompleksowego szyfrowania Ty i Twój kontakt ufacie swojemu serwerowi poczty e-mail, że nie będzie czytać ani manipulować waszymi wiadomościami i nie będzie przekazywać ich osobom trzecim.
- -W każdym razie nie możesz zrobić nic innego, jak zaakceptować ostrzeżenie. Usuń także kontakt z aktywnej grupy oznaczonej zielonym znacznikiem, którą znajdziesz w sekcji „Współdzielone czaty” w profilu kontaktu. Dzięki temu twój kontakt nie otrzyma „nieczytelnych” wiadomości.
- -Jeśli kontakt usunął Delta Chat z powodu błędów lub niepożądanego zachowania, rozważ opublikowanie postu na naszym forum pomocy, aby pomóc nam zidentyfikować i rozwiązać typowe problemy. Dzięki!
-Tak, Delta Chat korzysta z bezpiecznego podzbioru OpenPGP i wyświetla wskaźnik bezpieczeństwa kłódki na wiadomości tylko wtedy, gdy cała wiadomość jest prawidłowo zaszyfrowana i podpisana. Na przykład „Odłączone podpisy” nie są traktowane jako bezpieczne.
+Tak, Delta Chat korzysta z bezpiecznego podzbioru OpenPGP, który wymaga prawidłowego zaszyfrowania i podpisania całej wiadomości. Na przykład „Odłączone podpisy” nie są traktowane jako bezpieczne.
OpenPGP samo w sobie nie jest niebezpieczne. Większość publicznie omawianych problemów związanych z bezpieczeństwem OpenPGP tak naprawdę wynika ze złej użyteczności lub złej implementacji narzędzi, lub aplikacji (lub obu). Szczególnie ważne jest rozróżnienie pomiędzy OpenPGP, standardem szyfrowania IETF, a GnuPG (GPG), narzędziem wiersza poleceń implementującym OpenPGP. Wiele publicznych komentarzy krytycznych na temat OpenPGP tak naprawdę omawia GnuPG, którego Delta Chat nigdy nie używał. Delta Chat korzysta raczej z implementacji OpenPGP Rust rPGP, dostępnej jako niezależny pakiet „pgp” i poddanej audytowi bezpieczeństwa w 2019 i 2024 roku.
@@ -764,16 +739,14 @@ nadal będziesz mógł pisać, ale nie będziesz już powiadamiany o żadnych noNawet jeśli nie ma gwarancji, że twoje wiadomości będą zaszyfrowane metodą end-to-end, nadal są chronione przed dostawcami Internetu, takimi jak operatorzy komórkowi lub telewizji kablowej. Jednakże dostawcy poczty e-mail zarówno twoi, jak i twojego odbiorcy mogą czytać, analizować, a nawet modyfikować twoje wiadomości, w tym wszelkie załączniki, jeśli nie są one w pełni zaszyfrowane.
+Jeśli wysyłasz lub odbierasz wiadomości e-mail bez szyfrowania end-to-end (korzystając z klasycznego serwera poczty), są one nadal chronione przed operatorami komórkowymi lub kablowymi, którzy nie mogą ich czytać ani modyfikować. Jednak zarówno twoi dostawcy poczty e-mail, jak i dostawcy poczty e-mail odbiorcy mogą czytać, analizować lub modyfikować twoje wiadomości, w tym wszelkie załączniki.
Delta Chat domyślnie korzysta ze ścisłego szyfrowania TLS, które zabezpiecza połączenia pomiędzy twoim urządzeniem a dostawcą poczty e-mail. Cała obsługa TLS Delta Chat została poddana niezależnemu audytowi bezpieczeństwa. Co więcej, połączenie między tobą a dostawcą poczty e-mail odbiorcy będzie zazwyczaj również szyfrowane. Jeśli zaangażowane serwery poczty e-mail obsługują MTA-STS, pomiędzy dostawcami poczty e-mail będzie egzekwowane szyfrowanie transportu. W takim przypadku komunikacja Delta Chat nigdy nie będzie udostępniana w Internecie w postaci zwykłego tekstu, nawet jeśli wiadomość nie została zaszyfrowana metodą end-to-end.
- -Pamiętaj, że utrzymywanie gwarantowanego szyfrowania typu end-to-end oprócz szyfrowania TLS zapewnia wszechstronne bezpieczeństwo między urządzeniami twoimi i odbiorców. Nawet twój dostawca poczty e-mail lub Internetu nie będzie w stanie przeczytać ani zmodyfikować twoich wiadomości.
Delta Chat chroni większość metadanych wiadomości, umieszczając następujące informacje w całkowicie zaszyfrowanej części wiadomości:
+W przeciwieństwie do większości innych komunikatorów, aplikacje Delta Chat nie przechowują żadnych metadanych dotyczących kontaktów ani grup na serwerach, również w formie zaszyfrowanej. Zamiast tego wszystkie metadane grup są szyfrowane metodą end-to-end i przechowywane wyłącznie na urządzeniach użytkowników końcowych.
+ +Serwery poczty e-mail widzą zatem tylko:
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
zawierający polecenia bezpiecznego łączeniadatę wysłania wiadomości,
+adresy nadawcy i odbiorcy,
+oraz rozmiar wiadomości.
+Serwery poczty e-mail nie mają dostępu do chronionych metadanych, ale widzą datę wiadomości, jej rozmiar oraz, co ważniejsze, adresy nadawcy i odbiorcy. Serwery poczty e-mail potrzebują adresów odbiorców, aby kierować i dostarczać wiadomości do urządzeń odbiorców.
+Wszystkie pozostałe metadane dotyczące wiadomości, kontaktów i grup znajdują się w zaszyfrowanej metodą end-to-end części wiadomości.
Zarówno w celu ochrony przed serwerami poczty e-mail gromadzącymi metadane, jak i przed zagrożeniem przejęcia urządzenia, zalecamy użycie zoptymalizowanej instancji serwera poczty e-mail Delta Chat w celu tworzenia pseudonimowych kont tymczasowych poprzez skanowanie kodów QR. Pamiętaj, że aplikacje Delta Chat na wszystkich platformach obsługują wiele kont, dzięki czemu możesz z łatwością korzystać z kont „1-tygodniowych” lub „1-miesięcznych” związanych z konkretnymi działaniami obok konta „głównego”, wiedząc, że wszystkie tymczasowe dane konta wraz ze wszystkimi metadanymi zostaną usunięte. Co więcej, jeśli urządzenie zostanie przejęte, nie będzie można łatwo zidentyfikować kontaktów korzystających z tymczasowych kont e-mail, w porównaniu z komunikatorami, które ujawniają numery telefonów w grupach czatów, które z kolei często są powiązane z tożsamością prawną.
+Zarówno w celu ochrony przed serwerami poczty e-mail gromadzącymi metadane, jak i przed zagrożeniem przejęcia urządzenia, zalecamy użycie przełącznika chatmail do tworzenia profili czatu z losowymi adresami e-mail do przesyłania. Pamiętaj, że aplikacje Delta Chat na wszystkich platformach obsługują wiele kont, dzięki czemu możesz z łatwością korzystać z kont „1-tygodniowych” lub „1-miesięcznych” związanych z konkretnymi działaniami obok konta „głównego”, wiedząc, że wszystkie tymczasowe dane konta wraz ze wszystkimi metadanymi zostaną usunięte. Co więcej, jeśli urządzenie zostanie przejęte, kontakty czatu korzystające z profili krótkotrwałych nie będą mogły zostać łatwo zidentyfikowane.
-Możesz sprawdzić stan szyfrowania end-to-end ręcznie w oknie dialogowym „Szyfrowanie” (profil użytkownika w systemie Android/iOS lub kliknij prawym przyciskiem myszy element listy czatu użytkownika na komputerze). Delta Chat pokazuje tam dwa odciski palców. Jeśli te same odciski palców pojawią się u ciebie i urządzeniu twojego kontaktu, połączenie jest bezpieczne.
- -Nie, jeszcze nie.
-Mała kłódka w dymku wiadomości oznacza, że wiadomość od danego nadawcy została prawidłowo zaszyfrowana. Jeśli nie ma kłódki, wiadomość nie została prawidłowo zaszyfrowana metodą end-to-end, najprawdopodobniej dlatego, że nadawca korzysta z aplikacji lub interfejsu poczty internetowej bez obsługi szyfrowania typu end-to-end.
- -Komunikator Signal wprowadził funkcję „Sealed Sender” w 2018 roku, aby infrastruktura serwerowa nie wiedziała, kto wysyła wiadomość do grupy odbiorców. Jest to szczególnie ważne, ponieważ serwer Signal zna numer telefonu komórkowego każdego konta, który zazwyczaj jest powiązany z identyfikatorem paszportu.
-Jeśli kontakt korzysta z aplikacji e-mail bez Autocrypt, wszystkie wiadomości od tego kontaktu (w czacie grupowym lub 1:1) nie będą w pełni szyfrowane, w związku z czym nie będą wyświetlane z „kłódką” przy wiadomościach. Pamiętaj, że nawet jeśli twoje kontakty korzystają z Delta Chat na swoim koncie, mogą również używać na tym koncie aplikacji e-mail bez Autocrypt, co może powodować sporadyczne wysyłanie niezaszyfrowanych wiadomości. Odpowiadanie niezaszyfrowanych wiadomości na niezaszyfrowane wiadomości jest wymagane przez funkcję Autocrypt, aby zapobiec nieczytelnym wiadomościom po stronie twoich kontaktów i ich aplikacji e-mail bez Autocrypt.
- -Jeśli potrzebujesz bezpiecznie, kompleksowo zaszyfrowanego czatu z kontaktem, który korzysta ze swojego konta zarówno w Delta Chat, jak i w aplikacjach bez Autocrypt (np. poczta internetowa), najlepiej skonfigurować z nim gwarantowane szyfrowanie typu end-to-end, a następnie utworzyć gwarantowany zaszyfrowany end-to-end czat grupowy z wami dwoma jako członkami. W tym czacie grupowym wszystkie wiadomości będą w pełni szyfrowane, nawet jeśli bezpośredni czat między wami zawiera ostrzeżenie „…wysłano wiadomość z innego urządzenia”.
- -Najlepszym sposobem, aby mieć pewność, że każda wiadomość jest kompleksowo zaszyfrowana, a metadane usunięte tak szybko, jak to możliwe, jest korzystanie z czatów z gwarantowanym szyfrowaniem end-to-end i włączonymi znikającymi wiadomościami.
- -Gwarantowane szyfrowane metodą end-to-end czaty chronią przed atakami MITM attacks, a włączenie znikających wiadomości powoduje usunięcie wiadomości z serwera po upływie czasu skonfigurowanego przez użytkownika.
- -Jeśli nie potrzebujesz dłuższej kopii wiadomości na serwerze, możesz także włączyć opcję „automatycznie usuń wiadomości z serwera”.
+Nawet jeśli przekaźniki chatmail nie proszą o żadne prywatne dane (w tym numery telefonów), warto chronić metadane relacji między adresami. Nie przewidujemy poważniejszych problemów w korzystaniu z losowych, jednorazowych adresów e-mail do wysyłania wiadomości w tajemnicy, ale wdrożenie tej funkcji nie zostało jeszcze uznane za priorytetowe.
Nie, Delta Chat nie obsługuje funkcji Perfect Forward Secrecy (PFS). Oznacza to, że jeśli twój prywatny klucz deszyfrujący Delta Chat wycieknie i ktoś zdobędzie twoje wcześniejsze wiadomości w trakcie przesyłania, będzie mógł je odszyfrować i odczytać przy użyciu ujawnionego klucza deszyfrowania.
+Nie, jeszcze nie.
-Należy jednak pamiętać, że jeśli ktoś zdobędzie twoje klucze deszyfrujące, zazwyczaj będzie mógł również uzyskać twoje wiadomości, niezależnie od tego, czy obowiązuje zasada Perfect Forward Secrecy, czy nie. Typową sytuacją w świecie rzeczywistym w przypadku wycieku kluczy deszyfrujących jest przejęcie urządzenia, które omawiamy w naszej odpowiedzi na temat przejęcia metadanych i urządzenia.
+Delta Chat obecnie nie obsługuje mechanizmu Perfect Forward Secrecy (PFS). Oznacza to, że jeśli twój prywatny klucz deszyfrujący zostanie ujawniony, a ktoś zdobędzie twoje wcześniejsze wiadomości w trakcie transmisji, będzie mógł je odszyfrować i odczytać za pomocą ujawnionego klucza deszyfrującego. Należy pamiętać, że mechanizm Forward Secrecy zwiększa bezpieczeństwo tylko w przypadku usuwania wiadomości. W przeciwnym razie osoba, która uzyska twoje klucze deszyfrujące, zazwyczaj będzie mogła uzyskać dostęp do wszystkich nieusuniętych wiadomości i nie będzie musiała odszyfrowywać żadnych wcześniej zebranych wiadomości.
-Możliwe, że Delta Chat ewoluuje, aby wspierać Perfect Forward Secrecy, ponieważ OpenPGP to tylko kontener na zaszyfrowane wiadomości, ale zarządzanie kluczami szyfrowania (a tym samym rotacja kluczy lub „zapadanie kluczy”) mogłoby być zorganizowane w elastyczny sposób. Zobacz prototyp PFS firmy Seqouia, aby zapoznać się z istniejącymi eksperymentami w społeczności implementatorów OpenPGP.
+Opracowaliśmy metodę Forward Secrecy, która przeszła wstępną analizę niektórych kryptografów i ekspertów ds. wdrożeń, ale oczekuje na bardziej formalne opracowanie, które potwierdzi jej niezawodne działanie w federacyjnym przesyłaniu wiadomości i w przypadku korzystania z wielu urządzeń, zanim zostanie zaimplementowana w rdzeniu chatmail, co uczyniłoby ją dostępną we wszystkich klientach chatmail.
-To zależy od tego, co jest dla ciebie ważne. Delta Chat nie obsługuje PFS tak jak Signal, ale zapewnia gwarantowane szyfrowane end-to-end czatów, które jest zabezpieczeniem przed zaatakowanymi serwerami lub uszkodzonymi sieciami. Signal i większość innych komunikatorów obsługujących PFS nie zapewniają praktycznego schematu ochrony czatów grupowych przed atakami sieciowymi, które są prawdopodobnie bardziej niepokojące niż potencjalny atakujący, który przejmuje twój telefon i prywatne ustawienia szyfrowania i w ten sposób nie twoje wiadomości i mimo to ma pełny zapis wszystkich poprzednio zaszyfrowanych wiadomości.
+Nie, jeszcze nie.
-W każdym razie szyfrowanie end-to-end Delta Chat wykorzystuje bezpieczny podzbiór OpenPGP, który został poddany niezależnemu audytowi bezpieczeństwa.
+Delta Chat korzysta z biblioteki Rust OpenPGP rPGP, która obsługuje najnowszy projekt OpenPGP IETF Post-Quantum-Cryptography. Planujemy dodać obsługę PQC do rdzenia chatmail po sfinalizowaniu projektu w IETF we współpracy z innymi implementatorami OpenPGP.
+ +Możesz sprawdzić stan szyfrowania end-to-end ręcznie w oknie dialogowym „Szyfrowanie” (profil użytkownika w systemie Android/iOS lub kliknij prawym przyciskiem myszy element listy czatu użytkownika na komputerze). Delta Chat pokazuje tam dwa odciski palców. Jeśli te same odciski palców pojawią się u ciebie i urządzeniu twojego kontaktu, połączenie jest bezpieczne.
Za pomocą listy rozgłoszeniowej możesz wysłać wiadomość do wielu odbiorców naraz; odbiorcy nie mogą odpowiedzieć na tej liście. +Listy rozgłoszeniowe są nadal wysoce eksperymentalne i bardzo prawdopodobne, że zostaną zastąpione czymś innym, bądźcie czujni :)
Uwaga: Zmiana adresów e-mail jest tymczasowo wyłączona +z powodu trwających zmian w rdzeniu DeltaChat. +Powinna być ponownie dostępna za kilka miesięcy.
+Zmień swój adres w „Ustawienia → Zaawansowane → Hasło i konto” i wprowadź hasło do swojego nowego konta (i jeśli to konieczne, ustawienia serwera). Otrzymasz informację o przeniesieniu na nowy adres. Dodatkowe powiadomienie pojawi się również na czacie „Komunikaty urządzenia”.
@@ -1286,17 +1231,17 @@ Oto, co robi Delta Chat z tymi uprawnieniami: Jednak niektórzy dostawcy potrzebują specjalnych opcji, aby działać poprawnie, zobacz Przegląd dostawcówAutocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -968,7 +900,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1033,10 +963,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -If you don’t need a longer-lived copy of your messages on the server, -you can also turn on “delete messages from server automatically”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1752,19 +1618,19 @@ No entanto, alguns provedores precisam de opções especiais para funcionar corr ver Visão Geral dos Provedores
Autocrypt используется для автоматической
-установки сквозного шифрования при работе с контактами и групповыми чатами.
-Autocrypt использует ограниченное и безопасное подмножество стандарта OpenPGP.
-Сообщения, зашифрованные сквозным шифрованием, помечаются замком
-.
Delta Chat использует безопасное подмножество стандарта OpenPGP +для реализации автоматического сквозного шифрования c помощью следующих протоколов:
-Протоколы Secure-Join
-используются для создания чатов с гарантированным сквозным шифрованием,
-которое защищает от сетевых атак и скомпрометированных серверов.
-Чаты, отмеченные зелёной галочкой
-
-гарантируют сквозное шифрование сообщений.
Secure-Join +для обмена информацией о настройке шифрования через сканирование QR-кода или “ссылок-приглашений”.
+Autocrypt используется для автоматической +настройки сквозного шифрования между контактами и всеми членами группового чата.
+Обмен контактом в +чате +позволяет получателям настроить сквозное шифрование с этим контактом.
+Delta Chat не запрашивает, не публикует и не взаимодействует с какими-либо серверами ключей OpenPGP.
Сквозное шифрование гарантировано, если рядом с заголовком чата стоит зелёная галочка:
- -Все сообщения в Delta Chat по умолчанию шифруются сквозным шифрованием. +С момента выхода серии релизов Delta Chat версии 2 (июль 2025 года) +на сообщениях со сквозным шифрованием больше не отображаются замки или другие подобные индикаторы.
-Если у вас есть второй канал связи с вашим собеседником, -например, видеочат или другой мессенджер, -вы можете создать ссылку-приглашение.
+Если вы используете стандартные ретрансляторы chatmail, +невозможно получать или отправлять сообщения без сквозного шифрования.
-Если вы встретились лично с собеседником, -вы можете показать ему свой QR-код.
+Если же вы создаёте профиль с использованием обычного почтового сервера,
+то можете отправлять и получать сообщения без сквозного шифрования.
+Такие сообщения, не имеющие сквозного шифрования, отмечаются значком электронной почты
+.
Вы можете отправить ссылку-приглашение через другой личный чат, +показать QR-код приглашения, когда вы рядом или во время видеозвонка, +или нажать на “контакт”, которым поделились в чате.
-Позвольте вашему собеседнику отсканировать QR-код +
Попросите вашего собеседника отсканировать QR-код с помощью приложения Delta Chat, или нажмите “Копировать” или “Поделиться”, чтобы создать ссылку-приглашение и отправьте её вашему собеседнику.
-Теперь ожидайте, пока сообщения Secure-Join будут переданы между обоими устройствами.
+Теперь дождитесь, пока устанавливается сквозное шифрование.
Если оба устройства находятся в сети,
-обе стороны в конечном итоге увидят (групповой или прямой) чат с зелёной галочкой
-
-рядом с названием.
Если оба участника онлайн, они вскоре увидят (групповой или прямой) чат +и смогут начать защищённую переписку.
Если одно из устройств не подключено к сети, зелёные галочки появятся только после того, -как устройство снова подключится к Интернету -и сетевой протокол Secure-Join будет завершён.
+Если одна из сторон не в сети или имеет плохое соединение, +возможность переписки будет отложена до восстановления связи.
Поздравляем!
-Теперь вы будете автоматически использовать гарантированное сквозное шифрование
-с этим контактом, и вы оба сможете добавлять друг друга в группы, отмеченные зелёной галочкой
-,
-тем самым автоматически распространяя гарантированное сквозное шифрование среди её участников.
Чаты, помеченные зелёными галочками +
В профиле контакта может отображаться зелёная галочка
-означают, что все сообщения в чате будут зашифрованы сквозным шифрованием
-и не могут быть прочитаны или изменены скомпрометированными серверами электронной почты или интернет-провайдерами.
-Присоединение к групповым чатам с зелёной галочкой
-безопасно распространяет информацию о шифровании всех участников (и зелёные галочки)
-таким образом, чтобы гарантировать сквозное шифрование в группе и между её участниками.
Профили контактов с зелёной галочкой
-
-означают, что отправка сообщений контакту в настоящее время гарантированно зашифрована сквозным шифрованием.
-Каждый контакт с зелёной галочкой либо совершил с вами прямое QR-сканирование,
-либо был представлен другим контактом с зелёной галочкой.
-Знакомство происходит автоматически при добавлении участников в группы.
-Тот, кто добавляет контакт в группу, отмеченную зелёной галочкой, становится представителем
-для тех участников, которые еще не знают о добавленном контакте.
-В профиле контакта можно несколько раз нажать на текст “Представлен …” несколько раз
-пока не дойдёте до того, с кем вы непосредственно провели QR-сканирование.
Обратите внимание, что в профиле контакта вы можете увидеть и присоединённых знакомых, -но в заголовке профиля нет зелёной галочки. -Обычно это означает, что контакт “отправил сообщение с другого устройства”.
+и строка “Подтверждён пользователем”. +Каждый контакт с зелёной галочкой либо выполнил непосредственное сканирование QR-кода с вами, +либо был подтверждён другим контактом с зелёной галочкой. +Подтверждения происходят автоматически при добавлении участников в группы. +Тот, кто добавляет контакт с зелёной галочкой в группу, где только участники с зелёными галочками, +становится подтверждающим. +В профиле контакта вы можете последовательно нажимать на текст “Подтверждён …” до тех пор, +пока не дойдёте до того, с кем вы напрямую выполнили сканирование QR-кода.Для более подробного обсуждения “гарантированного сквозного шифрования” пожалуйста, обратитесь к протоколам Secure-Join и прочитайте о “Проверенных группах”, техническом термине, который здесь называется “группами с зелёной галочкой” или чатами с “гарантированным сквозным шифрованием”.
-Ваш чат с контактом утратил гарантированное сквозное шифрование. -Зелёная галочка была удалена для этого чата и контакта, и когда вы увидели предупреждение. -Если вы обнаружили внезапное прекращение гарантированного сквозного шифрования -для этого контакта, не принимайте предупреждение! -Вместо этого свяжитесь со своим контактом по второму каналу, -например, видеозвонок, другой мессенджер или телефонный звонок, -чтобы узнать, что произошло.
- -Если ваш контакт стал причиной потери гарантированного сквозного шифрования, -пожалуйста, ознакомьтесь с распространёнными причинами и способами их устранения в следующих параграфах. -Независимо от этого, все остальные чаты, отмеченные зелёной галочкой, остаются гарантированно зашифрованными сквозным шифрованием, -даже если этот контакт является его участником.
- -Ваш контакт использует Delta Chat на втором устройстве (телефоне или ноутбуке)
- -Если у него есть другое устройство с запущенным приложением Delta Chat, -ему следует удалить учётную запись с нового устройства -и добавить его как второе устройство, как описано здесь. -После того, как он отправит вам сообщение, предупреждение исчезнет -и гарантированное шифрование будет установлено на обоих устройствах вашего собеседника.
- -Ваш контакт переустановил Delta Chat, используя старые учетные данные для входа
- -Если у него есть файл резервной копии, -ему следует удалить профиль с нового устройства -и вместо этого импортировать резервную копию для восстановления своего профиля. -После того, как он отправит вам сообщение, предупреждение исчезнет, -и гарантированное шифрование будет восстановлено для этого контакта.
- -Если у него нет файла резервной копии, лучше всего выполнить сканирование QR-кода -с вашим собеседником, чтобы восстановить гарантированное сквозное шифрование.
- -Ваш контакт отправил письмо через интерфейс веб-почты или другое приложение электронной почты -и снова вернулся к использованию Delta Chat.
- -Если вы уверены, что ваш контакт иногда использует веб-почту -или другое приложение электронной почты, в котором отсутствует сквозное шифрование, -то вы можете принять предупреждение. -Как только контакт снова начнёт использовать Delta Chat, -гарантированное сквозное шифрование будет автоматически восстановлено.
- -Ваш контакт полностью прекратил использование Delta Chat
- -Иногда оставаться на связи важнее, чем сквозное шифрование. -“Протокол защиты транспортного уровня” (TLS) всё ещё может существенно защитить -конфиденциальность ваших сообщений между вашим устройством и сервером электронной почты. -Но без сквозного шифрования вы и ваш контакт должны доверять серверу электронной почты, -который не должен читать и манипулировать вашими сообщениями, и не передавать их третьим лицам.
- -В любом случае, вы ничего не можете сделать, кроме как принять предупреждение. -Также удалите контакт из любой активной группы, отмеченной зелёной галочкой, -которую можно найти в разделе “Общие чаты” в профиле контакта. -Это избавит ваш контакт от получения “не читаемых” сообщений.
- -Если контакт удалил Delta Chat из-за ошибок или нежелательного поведения, -пожалуйста, подумайте о том, чтобы поделиться этой информацией на нашем форуме поддержки, -чтобы помочь нам выявить и устранить общие проблемы. Спасибо!
-Даже если не гарантируется сквозное шифрование ваших сообщений, -они все равно защищены от интернет-провайдеров, сотовых операторов или кабельных компаний. -Однако провайдеры электронной почты, ваш и ваших получателей -могут читать, анализировать или даже изменять ваши сообщения, -включая любые вложения, -если они не зашифрованы сквозным шифрованием.
+Если вы отправляете или получаете электронные сообщения без сквозного шифрования (используя классический почтовый сервер), +они всё равно защищены от операторов сотовой связи или интернет-провайдеров, которые не могут прочитать или изменить ваши электронные сообщения. +Однако и ваш почтовый провайдер, и почтовый провайдер вашего получателя +могут читать, анализировать или изменять ваши сообщения, включая любые вложения.
Delta Chat по умолчанию использует строгое TLS-шифрование, @@ -1032,10 +961,6 @@ Delta Chat вместо этого использует реализацию Ope то между провайдерами электронной почты будет применяться протокол защиты транспортного уровня. В этом случае сообщения Delta Chat никогда не будут переданы в открытом виде через Интернет, даже если сообщение не было зашифровано сквозным шифрованием.
- -Обратите внимание, что поддержание гарантированного сквозного шифрования поверх шифрования TLS -обеспечивает полную безопасность между вашими устройствами и устройствами получателя. -Ни ваш провайдер электронной почты, ни провайдер Интернета не смогут прочитать или изменить ваши сообщения.
Delta Chat защищает большинство метаданных сообщений, помещая следующую информацию, -в зашифрованную сквозным шифрованием часть сообщений:
+В отличие от большинства других мессенджеров, +приложения Delta Chat не сохраняют никакие метаданные о контактах или группах на серверах, даже в зашифрованной форме. +Вместо этого все групповые метаданные шифруются сквозным шифрованием и хранятся исключительно на устройствах конечных пользователей.
+ +Поэтому, почтовые серверы имеют доступ только к
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
); Участник-группы-чата-добавлен (Chat-Group-Member-Added
)Secure-Join
, содержащий команды безопасного соединениядате сообщения,
+адресам отправителя и получателя
+и размеру сообщения.
+Серверы электронной почты не получают доступ к этим защищённым метаданным, -но они видят дату сообщения, а также его размер, -и, что более важно, адреса отправителя и получателя. -Серверам электронной почты нужны адреса получателей для маршрутизации и -доставки сообщений на устройства получателей.
+Все прочие метаданные сообщений, контактов и групп содержатся в части сообщений, защищённой сквозным шифрованием.
Для защиты от серверов электронной почты, собирающих метаданные, а также от угрозы конфискации устройства, -мы рекомендуем использовать сервер chatmail, -для создания безымянных (псевдонимных), временных профилей через сканирование QR-кодов. +мы рекомендуем использовать релей chatmail +для создания чат-профилей с использованием случайных электронных адресов для передачи сообщений. Обратите внимание, что приложения Delta Chat на всех платформах поддерживают несколько профилей, -так что вы можете легко использовать отдельные профили, для конкретной ситуации, -помимо вашего “основного” профиля, +так что вы можете легко использовать отдельные профили, для конкретной ситуации, помимо вашего “основного” профиля, зная, что все их данные, вместе с метаданными, будут удалены. -Кроме того, если устройство будет конфисковано, контакты, использующие временные профили, -не могут быть легко идентифицированы, в отличие от мессенджеров, которые раскрывают -номера телефонов в групповых чатах, которые часто связаны с реальными личностями.
+Кроме того, если устройство изъято, контакты, использующие временные профили, +не могут быть легко идентифицированы. -Нет, пока нет.
+ +Мессенджер Signal внедрил функцию “Sealed Sender” (Засекреченный отправитель) в 2018 году, +чтобы их серверная инфраструктура не имела информации о том, кто отправляет сообщение группе получателей. +Это особенно важно, поскольку сервер Signal знает мобильный номер каждого аккаунта, +который обычно привязан к паспортным данным.
+ +Даже если релеи chatmail +не запрашивают никаких личных данных (включая телефонные номера), +всё равно может быть полезно защитить реляционные метаданные между адресами +Мы не видим серьёзных проблем в использовании случайных одноразовых электронных адресов для функции sealed sender, +но реализация пока не определена как приоритетная задача.
+ +Нет, пока нет.
+ +На данный момент, Delta Chat не поддерживает Perfect Forward Secrecy (PFS) (Совершенную прямую секретность). +Это означает, что если ваш приватный ключ дешифрования будет скомпрометирован, +и кто-то собрал ваши предыдущие сообщения во время передачи, +они смогут расшифровать и прочитать их, используя скомпрометированный ключ дешифрования. +Обратите внимание, что Forward Secrecy (Прямая секретность) повышает безопасность только если вы удаляете сообщения. +В противном случае, тот, кто получает ваши ключи дешифрования +также может получить все ваши не удалённые сообщения +и ему даже не нужно расшифровывать какие-либо ранее собранные сообщения.
+ +Мы разработали подход к Forward Secrecy (Прямой секретности), который прошёл +первичную проверку некоторыми криптографами и экспертами по реализации +но требует более формального описания +чтобы убедиться, что он надёжно работает в федеративном обмене сообщениями и при использовании нескольких устройств, +прежде чем он может быть внедрён в ядро chatmail, +что сделает его доступным во всех клиентах clients.
+ +Нет, пока нет.
+ +Delta Chat использует библиотеку OpenPGP на Rust rPGP, +которая поддерживает последний черновик IETF Post-Quantum-Cryptography OpenPGP. +Мы планируем добавить поддержку PQC в ядро chatmail после того, как черновик будет окончательно утвержден в IETF +в сотрудничестве с другими разработчиками OpenPGP.
+ +Маленький значок замка в сообщении означает, -что сообщение было правильно зашифровано сквозным шифрованием от данного отправителя. -Если замка нет, сообщение не было правильно зашифровано, -возможно, потому что отправитель использует приложение или веб-интерфейс электронной почты -без поддержки сквозного шифрования.
- -Если контакт использует приложение электронной почты, не поддерживающее Autocrypt, -все сообщения, включающие этого контакта (в групповом или личном 1:1 чате), -не будут зашифрованы сквозным шифрованием, и поэтому не будут иметь “значок замка” в сообщениях. -Обратите внимание, что даже если ваши контакты используют Delta Chat на своем аккаунте, -они также могут использовать приложение электронной почты, не поддерживающее Autocrypt, -на том же аккаунте, что может привести к периодически незашифрованным сообщениям. -Ответ на незашифрованные сообщения незашифрованным сообщением является обязательным в Autocrypt, -чтобы предотвратить появление нечитаемых сообщений на стороне ваших контактов -и их приложении электронной почты, которое не поддерживает Autocrypt.
- -Если вам нужен зашифрованный сквозным шифрованием чат с контактом, -который использует свой адрес электронной почты как с Delta Chat, так и с приложениями, не поддерживающими Autocrypt (например, веб-почтой), -лучше всего настроить с ним гарантированное сквозное шифрование -и затем создать гарантированно зашифрованный сквозным шифрованием групповой чат с вами двумя как участниками. -В этом групповом чате все сообщения будут зашифрованы сквозным шифрованием, -даже если прямой чат между вами двумя имеет предупреждение -“… отправил сообщение с другого устройства”.
- -Лучший способ обеспечить сквозное шифрование каждого сообщения, -где метаданные удаляются как можно быстрее, -это использовать чаты с гарантированным сквозным шифрованием -и включить исчезающие сообщения.
- -Чаты с гарантированным сквозным шифрованием защищают от атак “человек посередине”, -а включение исчезающих сообщений удаляет сообщения -на сервере через заданное пользователем время.
- -Если вам не нужна долгоживущая копия ваших сообщений на сервере, -вы также можете включить “удалять сообщения с сервера автоматически”.
- -Нет, Delta Chat не поддерживает совершенную прямую секретность (PFS). -Это означает, что если ваш личный ключ дешифрования Delta Chat будет скомпрометирован, -и кто-то собрал ваши предыдущие сообщения, переданные по сети, -то они смогут расшифровать и прочитать их с помощью скомпрометированного ключа дешифрования.
- -Обратите внимание, если кто-то получит доступ к вашим ключам дешифрования, -они, как правило, также смогут получить доступ к вашим сообщениям, -независимо от того, используется ли совершенная прямая секретность или нет. -Типичная реальная ситуация для утечки ключей дешифрования - это изъятие устройства, -о чём мы говорим в нашем ответе о метаданных и изъятии устройства.
- -Возможно, Delta Chat будет развиваться в направлении поддержки совершенной прямой секретности (PFS), -поскольку OpenPGP является всего лишь контейнером для зашифрованных сообщений, -но управление ключами шифрования (и, следовательно, ротация ключей или “переключение” ключей) -могут быть организованы гибкими способами. -См. прототип PFS Seqouia -для существующих экспериментов в сообществе разработчиков OpenPGP.
- -Это зависит от того, что для вас важно. -Delta Chat не поддерживает PFS, как Signal, -но обеспечивает гарантированно зашифрованные сквозным шифрованием чаты -защищенные от скомпрометированных серверов или поврежденных сетей. -Signal и большинство других мессенджеров, поддерживающих PFS, -не предоставляют практической схемы защиты групповых чатов от сетевых атак, -которые, возможно, вызывают большее беспокойство, -чем потенциальный злоумышленник, который захватывает ваш телефон и настройки персонального шифрования, -но почему-то не ваши сообщения, но при этом имеет полный отчет обо всех прошлых зашифрованных сообщениях.
- -В любом случае, сквозное шифрование Delta Chat использует безопасное подмножество OpenPGP -которое прошло независимую проверку безопасности.
-Список рассылки позволяет отправлять сообщения сразу нескольким адресатам; +получатели не могут отвечать в этом списке. +Функция списков рассылки пока что экспериментальная +и, скорее всего, в будущем будет заменена на что-то другое — следите за новостями. :)
Примечание: +Смена электронных адресов временно отключена +из-за продолжающихся изменений в ядре DeltaChat. +Функция должна снова заработать через несколько месяцев.
+Измените свой адрес в разделе “Настройки → Дополнительные параметры → Пароль и аккаунт” и @@ -1751,19 +1616,19 @@ Delta Chat.
Autocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -971,7 +903,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1036,10 +966,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
header containing secure join commandsthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -If you don’t need a longer-lived copy of your messages on the server, -you can also turn on “delete messages from server automatically”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1757,19 +1623,19 @@ Niektorí poskytovatelia však potrebujú na správne fungovanie špeciálne mo pozrite si Prehľad poskytovateľa
Autocrypt is used for automatically
-establishing end-to-end encryption with contacts and group chats.
-Autocrypt uses a limited and secure subset of the OpenPGP standard.
-End-to-End encrypted messages are marked with a padlock
-.
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-Secure-Join protocols
-are used for establishing chats with guaranteed end-to-end encryption
-which protects against network attacks and compromised servers.
-Chats marked with a green checkmark
-
-guarantee end-to-end encrypted messages.
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
All end-to-end encrypted messages carry a padlock:
- -End-to-end encryption is guaranteed if there is a green checkmark next to the chat title:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-If you have a second communication channel with your chat partner, -like a video chat or a different messenger, -you can generate an invite link.
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-If you are together in person, -you can show a QR code to your chat partner.
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
For direct 1:1 chat invitations, +
For direct 1:1 chat invitations,
tap the QR Code icon
on the Delta Chat app main screen.
Let your chat partner scan the QR image +
Ask your chat partner to scan the QR image with their Delta Chat app, or click “Copy” or “Share” to create an invite link and share it with your chat partner.
-Now wait while Secure-Join network messages are exchanged between both devices.
+Now wait while end-to-end encryption is getting established.
If both devices are online,
-both sides will eventually see a (group or direct) chat with a green checkmark
-
-next to the title.
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
If one of the devices is offline, the green checkmarks will only -appear later when the device is internet-connected again -and the Secure-Join network protocol completed.
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
Congratulations!
-You now will automatically use guaranteed end-to-end encryption
-with this contact and both of you can add each other to green-checkmarked groups
-,
-thereby automatically spreading guaranteed end-to-end encryption among its members.
Chat titles with green checkmarks +
A contact profile might show a green checkmark
-mean that all messages in the chat will be end-to-end encrypted
-and can not be read or altered by compromised e-mail servers or Internet providers.
-Joining green-checkmarked group chats
-safely spreads everybody’s encryption information (and green checkmarks)
-in a manner that guarantees end-to-end encryption in the group and among members.
Contact profiles with green checkmarks
-
-mean that messaging a contact is currently guaranteed to be end-to-end encrypted.
+and an “Introduced by” line.
Every green-checkmarked contact either did a direct QR-scan with you
or was introduced by a another green-checkmarked contact.
Introductions happen automatically when adding members to groups.
-Whoever adds a contact to a green-checkmarked group becomes an introducer
-to those members who didn’t yet know about the added contact.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
In a contact profile you can tap on the “Introduced by …” text repeatedly
until you get to the one with whom you directly did a QR-scan.
Note that in a contact profile you may see and tap introducers -but there is no green checkmark in the profile title. -This usually means that the contact “sent a message from another device”.
-For more in-depth discussion of “guaranteed end-to-end encryption” please see Secure-Join protocols and specifically read about “Verified Groups”, the technical term of what is called here “green-checkmarked” or “guaranteed end-to-end encrypted” chats.
-Your chat with a contact lost guaranteed end-to-end encryption. -The green checkmark was removed for this chat and contact when you see this warning. -If you find the sudden drop of guaranteed end-to-end encryption -surprising for this contact then don’t accept the warning! -Instead check with your contact through a second channel -like a video call, other messenger or a phone call, -to find out what happened.
- -If your contact actually caused the drop of guaranteed end-to-end encryption -please see the next paragraphs for common reasons and their mitigations. -Regardless, all other green-checkmarked chats remain guaranteed end-to-end encrypted -even if the contact is a member there.
- -Your contact is using Delta Chat on a second device (phone or laptop)
- -If they have another device with a Delta Chat app running, -they should remove the profile from the new device -and add it as a second device as described here. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is established with both devices of your contact.
- -Your contact reinstalled Delta Chat using their old account login
- -If they have a backup file, -they should remove the profile from the new device -and rather import the backup file to re-create their profile. -As soon as they message you afterwards, the warning will be gone -and guaranteed encryption is re-established for this contact.
- -If they don’t have a backup file, it’s best to perform a QR scan -with your chat partner to re-establish guaranteed end-to-end encryption.
- -Your contact sent a mail through a webmail interface or another e-mail app -and will get back to using Delta Chat soon again.
- -If you are sure that the contact sometimes uses webmail, -or another mail app lacking end-to-end encryption, -then you may accept the warning. -As soon as your contact uses Delta Chat again, -guaranteed end-to-end encryption will be automatically re-established.
- -Your contact stopped using Delta Chat entirely
- -Sometimes remaining in contact is more important than end-to-end encryption. -“Transport Layer Encryption” (TLS) may still meaningfully protect -the confidentiality of your messages between your device and the e-mail server. -But without end-to-end encryption you and your contact are trusting your e-mail server -to not read or manipulate your messages, and to not hand them to third parties.
- -In any case, you can not do much else than accept the warning. -Please also remove the contact from any active green-checkmarked group -which you can find in “Shared chats” in the Contact profile. -This spares your contact from getting “unreadable” messages.
- -If the contact removed Delta Chat because of buggy or undesirable behaviour, -please consider posting to our support forum -to help us identify and address common problems. Thanks!
-Yes, Delta Chat uses a secure subset of OpenPGP -and only displays a padlock security indicator on a message -if the whole message is properly encrypted and signed. +requiring the whole message to be properly encrypted and signed. For example, “Detached signatures” are not treated as secure.
OpenPGP is not insecure by itself. @@ -972,7 +904,7 @@ which was thankfully adopted in summer 2023.
Even if your messages are not guaranteed to be end-to-end encrypted, -they are still protected from Internet providers like cell or cable companies. -However, your and your recipient’s e-mail providers -may read, analyze or even modify your messages, -including any attachments, -if they are not end-to-end encrypted.
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat by default uses strict TLS encryption @@ -1037,10 +967,6 @@ If the involved e-mail servers support maintaining guaranteed end-to-end encryption on top of TLS encryption -provides pervasive safety between your and the recipient’s devices. -Not even your e-mail or Internet provider will be able to read or modify your messages.
Delta Chat protects most message metadata by putting the following information -into the end-to-end encrypted part of messages:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
që përmban urdhra për pjesëmarrje të siguruarthe message date,
+sender and receiver addresses
+and message size.
+E-Mail servers do not get access to this protected metadata -but they do see the message date as well as the message size, -and, more importantly, the sender and receiver addresses. -E-mail servers need receiver addresses to route and -deliver messages to recipient’s devices.
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
Both for protecting against metadata-collecting e-mail servers as well as against the threat of device seizure -we recommend to use a chatmail server -to create pseudonymous temporary profiles through QR-code scans. +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. Note that Delta Chat apps on all platforms support multiple profiles so you can easily use situation-specific profiles next to your “main” profile with the knowledge that all their data, along with all metadata, will be deleted. -Moreover, if a device is seized then contacts using temporary profiles -can not be identified easily, as compared to messengers which reveal -phone numbers in chat groups which in turn are often associated with legal identities.
+Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily. -You may check the end-to-end encryption status manually in the “Encryption” dialog -(user profile on Android/iOS or right-click a user’s chat-list item on desktop). -Delta Chat shows two fingerprints there. -If the same fingerprints appear on your own and your contact’s device, -the connection is safe.
- -No, not yet.
-A little padlock in a message bubble denotes -that the message was properly end-to-end encrypted from the given sender. -If there is no padlock, the message was not properly end-to-end encrypted -most likely because the sender uses an app or webmail interface -without support for end-to-end–encryption.
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-If a contact uses a non-Autocrypt e-mail app, -all messages involving this contact (in a group or 1:1 chat) -will not be end-to-end encrypted, and thus not show a “padlock” with messages. -Note that even if your contacts use Delta Chat on their account, -they might also use a non-Autocrypt e-mail app on that account -which then may cause intermittently unencrypted messages. -Replying unencrypted to unencrypted messages is mandated by Autocrypt -to prevent unreadable messages on the side of your contacts -and their non-Autocrypt e-mail app.
- -If you need a safely end-to-end encrypted chat with a contact -who is using their e-mail account both with Delta Chat and non-Autocrypt apps (e.g. webmail), -it’s best to setup guaranteed end-to-end encryption with them -and then create a guaranteed end-to-end encrypted group chat with you two as members. -In this group chat all messages will be end-to-end encrypted -even if the direct chat between you two has a -“… sent a message from another device” warning.
- -The best way to ensure every message is end-to-end encrypted, -and metadata deleted as quickly as possible -is using chats with guaranteed end-to-end encryption -and turning on disappearing messages.
- -Guaranteed end-to-end encrypted chats protect against MITM attacks -and turning on disappearing messages deletes the messages -on the server after a user-configured time.
- -Nëse s’ju duhet te shërbyesi një kopje jetëgjatë e mesazheve tuaj, -mund edhe të aktivizoni “fshiji automatikisht nga shërbyesi mesazhe”.
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
No, Delta Chat doesn’t support Perfect Forward Secrecy (PFS). -This means that if your Delta Chat private decryption key is leaked, +
No, not yet.
+ +Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, and someone has collected your prior in-transit messages, -they will be able to decrypt and read them using the leaked decryption key.
+they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages. -Note, however, that if anyone obtains to your decryption keys, -they will typically also be able to obtain your messages, -irrespective if Perfect Forward Secrecy is in place or not. -The typical real-world situation for leaked decryption keys is device seizure -which we discuss in our answer on metadata and device seizure.
- -It is possible that Delta Chat evolves to support Perfect Forward Secrecy, -because OpenPGP is just a container for encrypted messages -but encryption key management (and thus key rotation or key “ratcheting”) -could be organized in flexible ways. -See Seqouia’s PFS prototype -for existing experiments in the OpenPGP implementor community.
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-It depends on what is important to you. -Delta Chat does not support PFS like Signal does -but it provides guaranteed end-to-end encrypted chats -that are safe against compromised servers or corrupted networks. -Signal and most other PFS-supporting messengers do not provide -a practical scheme for protecting chat groups from network attacks -which are arguably more worrisome -than a potential attacker who seizes your phone and private encryption setup -but somehow not your messages, yet has a full record of all -past encrypted messages.
+No, not yet.
-In any case, Delta Chat’s end-to-end encryption uses a secure subset of OpenPGP -which has been independently security-audited.
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +You may check the end-to-end encryption status manually in the “Encryption” dialog +(user profile on Android/iOS or right-click a user’s chat-list item on desktop). +Delta Chat shows two fingerprints there. +If the same fingerprints appear on your own and your contact’s device, +the connection is safe.
2024 December, an NLNET-commissioned Evaluation of rPGP by Radically Open Security took place. -rPGP serves as the end-to-end encyption OpenPGP engine of Delta Chat. +rPGP serves as the end-to-end encryption OpenPGP engine of Delta Chat. Two advisories were released related to the findings of this audit:
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+Change your address in “Settings → Advanced → Password and Account” and @@ -1758,19 +1623,19 @@ Sidoqoftë, disa furnizues shërbimesh kanë nevojë për mundësi speciale, që të funksionojnë si duhet, shihni Provider Overview
Зверніть увагу, що Delta Chat має невелику систему push-повідомлень, що зберігає конфіденційність яка забезпечує “миттєву доставку” повідомлень на всі chatmail-сервери включаючи потенційний який ви можете налаштувати самостійно без нашого дозволу. Ласкаво просимо до потужності сумісної та масової системи чат-пошти та електронної пошти :)
-Autocrypt використовується для автоматичного встановлення наскрізного шифрування з контактами та груповими чатами.
-Autocrypt використовує обмежену і безпечну підмножину стандарту OpenPGP. Зашифровані наскрізним шифруванням повідомлення позначаються замком .
Delta Chat використовує [безпечну підмножину стандарту OpenPGP] (#openpgp-secure) для забезпечення автоматичного наскрізного шифрування за допомогою цих протоколів:
-Протоколи Secure-Join використовуються для створення чатів з гарантованим наскрізним шифруванням що захищає від мережевих атак і скомпрометованих серверів. Чати, відмічені зеленою галочкою гарантують наскрізне шифрування повідомлень.
Використовуйте Secure-Join щоб обмінюватися інформацією про налаштування шифрування, через сканування QR-коду або “посилання-запрошення”.
+Autocrypt використовується для автоматичного встановлення наскрізного шифрування між контактами і всіма учасниками групового чату.
+[Поширення контакту в чаті] (https://github.com/chatmail/core/blob/main/spec.md#attaching-a-contact-to-a-message) дозволяє отримувачам використовувати наскрізне шифрування з контактом.
+Delta Chat не запитує, не публікує і не взаємодіє з будь-якими серверами ключів OpenPGP.
Всі наскрізні зашифровані повідомлення мають навісний замок:
- -Наскрізне шифрування гарантується, якщо поруч із заголовком чату стоїть зелена галочка:
- -Всі повідомлення в Delta Chat за замовчуванням наскрізно зашифровані. Починаючи з версії 2 Delta Chat (липень 2025 року) на наскрізних зашифрованих повідомленнях більше немає замків або інших подібних маркерів.
-Якщо у вас є другий канал зв’язку з вашим партнером по чату, наприклад, відеочат або інший месенджер, ви можете згенерувати посилання-запрошення.
+Якщо ви використовуєте стандартні ретранслятори чату, неможливо отримувати або надсилати повідомлення без наскрізного шифрування.
-Якщо ви разом особисто, ви можете показати QR-код своєму співрозмовнику.
+Якщо ви створите профіль за допомогою класичного поштового сервера, ви зможете надсилати та отримувати повідомлення без наскрізного шифрування. Такі повідомлення без наскрізного шифрування позначаються значком електронної пошти .
Ви можете надіслати посилання-запрошення через інший приватний чат, показати QR-код запрошення, коли ви знаходитесь поруч один з одним або під час відеодзвінка, або натиснути на “контакт”, яким ви поділилися в чаті.
Для Запрошення до групи, торкніться назви групи чату, щоб побачити список її учасників, і виберіть “QR-код запрошення”.
Для прямих запрошень у чат 1:1, торкніться іконки QR-коду на головному екрані програми Delta Chat.
Для прямих запрошень у чат один-на-один, торкніться іконки QR-коду на головному екрані програми Delta Chat.
Дозвольте вашому партнеру по чату відсканувати QR-зображення -у своєму додатку Delta Chat, або натисніть “Копіювати” чи “Поділитися”, щоб створити посилання-запрошення і поділитися ним з вашим співрозмовником.
+Попросіть вашого партнера по чату відсканувати QR-зображення у своєму додатку Delta Chat, або натисніть “Копіювати” чи “Поділитися”, щоб створити посилання-запрошення і поділитися ним з вашим партнером по чату.
-Тепер зачекайте, поки між обома пристроями відбудеться обмін мережевими повідомленнями Secure-Join.
+Тепер зачекайте, поки встановиться наскрізне шифрування.
Якщо обидва пристрої онлайн, обидві сторони зрештою побачать (груповий або прямий) чат із зеленою галочкою поруч із заголовком.
Якщо обидві сторони онлайн, вони незабаром побачать (груповий або прямий) чат і можуть почати безпечно обмінюватися повідомленнями.
Якщо один з пристроїв не в мережі, зелені галочки з’являться пізніше, коли пристрій знову буде підключено до Інтернету а мережевий протокол Secure-Join буде завершено.
+Якщо одна зі сторін перебуває в офлайні або в поганій мережі, можливість спілкуватися в чаті затримується до відновлення з’єднання.
Вітаємо! Тепер ви автоматично використовуватимете гарантоване наскрізне шифрування з цим контактом, і ви обидва можете додавати один одного в групи, позначені зеленою галочкою , таким чином автоматично поширюючи гарантоване наскрізне шифрування серед її членів.
Вітаємо! +Тепер ви автоматично використовуватимете наскрізне шифрування з цим контактом. Якщо ви додасте один одного в групи чату, наскрізне шифрування буде встановлено між усіма учасниками.
Назви чатів із зеленими галочками означають, що всі повідомлення в чаті будуть наскрізно зашифровані і не можуть бути прочитані або змінені скомпрометованими поштовими серверами або інтернет-провайдерами.
-Приєднання до групових чатів із зеленими галочками безпечно поширює інформацію про шифрування (і зелені галочки) всіх учасників таким чином, що гарантує наскрізне шифрування в групі та між її учасниками.
Профілі контактів із зеленими галочками означають, що повідомлення контакту наразі гарантовано зашифровані наскрізним шифруванням. Кожен контакт із зеленою галочкою або зробив пряме QR-сканування з вами або був представлений іншим контактом, позначеним зеленою галочкою. Знайомство відбувається автоматично під час додавання учасників до груп. Той, хто додає контакт до групи, позначеної зеленою галочкою, стає представником для тих учасників, які ще не знали про доданий контакт. У профілі контакту ви можете кілька разів натиснути на текст “Представлений …” поки не потрапите до того, з ким ви безпосередньо зробили QR-сканування.
Зверніть увагу, що в профілі контакту ви можете бачити і натискати рекомендувачів але в заголовку профілю немає зеленої галочки. Зазвичай це означає, що контакт “надіслав повідомлення з іншого пристрою”.
+У профілі контакту може відображатися зелена галочка і рядок “Представлений”. Кожен контакт із зеленою галочкою або зробив пряме [QR-сканування] (#howtoe2ee) з вами або був представлений іншим контактом, позначеним зеленою галочкою. Знайомство відбувається автоматично під час додавання учасників до груп. Той, хто додає контакт із зеленою галочкою до групи, в якій є лише учасники із зеленою галочкою стає представником. У профілі контакту ви можете кілька разів натиснути на текст “Представлений …” поки не потрапите до того, з ким ви безпосередньо зробили [QR-сканування] (#howtoe2ee).
Для більш детального обговорення “гарантованого наскрізного шифрування” будь ласка, перегляньте Протоколи безпечного приєднання і, зокрема, прочитайте про “Перевірені групи”, технічний термін того, що тут називається чатами з “зеленою галочкою” або “гарантованим наскрізним шифруванням”.
-Ваш чат з контактом втратив гарантоване наскрізне шифрування. Зелену галочку було знято для цього чату та контакту, коли ви побачили це попередження. **Якщо ви вважаєте раптове зникнення гарантованого наскрізного шифрування несподіваним для цього контакту, не приймайте попередження! Замість цього зв’яжіться з контактом через другий канал наприклад, відеодзвінок, інший месенджер або телефонний дзвінок, щоб з’ясувати, що сталося.
- -Якщо ваш контакт дійсно спричинив втрату гарантованого наскрізного шифрування будь ласка, зверніться до наступних параграфів, щоб дізнатися про типові причини та способи їх усунення. Незважаючи на це, всі інші чати, позначені зеленою галочкою, залишаються гарантовано зашифрованими з кінця в кінець навіть якщо контакт є їхнім учасником.
- -Ваш контакт використовує Delta Chat на другому пристрої (телефоні або ноутбуці).
- -Якщо у них є інший пристрій із запущеним додатком Delta Chat, вони повинні видалити профіль з нового пристрою і додати його як другий пристрій, як описано тут. Як тільки вони напишуть вам повідомлення, попередження зникне і гарантоване шифрування буде встановлено на обох пристроях вашого контакту.
- -Ваш контакт перевстановив Delta Chat, використовуючи свій старий логін
- -Якщо у них є файл резервної копії, вони повинні видалити профіль з нового пристрою і, замість цього, імпортувати файл резервної копії для відновлення свого профілю. Як тільки вони напишуть вам повідомлення, попередження зникне і гарантоване шифрування буде відновлено для цього контакту.
- -Якщо у них немає резервної копії файлу, найкраще виконати QR-сканування з вашим співрозмовником, щоб відновити гарантоване кінцеве шифрування.
- -Ваш контакт надіслав листа через веб-інтерфейс або іншу поштову програму і незабаром повернеться до використання Delta Chat.
- -Якщо ви впевнені, що контакт іноді користується веб-поштою, або іншу поштову програму без наскрізного шифрування, ви можете прийняти попередження. Як тільки ваш контакт знову скористається Delta Chat, гарантоване наскрізне шифрування буде автоматично відновлено.
- -Ваш контакт повністю припинив користуватися Delta Chat.
- -Іноді залишатися на зв’язку важливіше, ніж наскрізне шифрування. “Шифрування на транспортному рівні” (TLS) все ще може ефективно захищати конфіденційність ваших повідомлень між вашим пристроєм і сервером електронної пошти. Але без наскрізного шифрування ви та ваш контакт довіряєте серверу електронної пошти не читати і не маніпулювати вашими повідомленнями, а також не передавати їх третім особам.
- -У будь-якому випадку, ви не можете зробити нічого іншого, окрім як прийняти попередження. Будь ласка, також видаліть контакт з будь-якої активної групи, позначеної зеленою галочкою які ви можете знайти в розділі “Загальні чати” в профілі контакту. Це позбавить ваш контакт від отримання “нечитабельних” повідомлень.
- -Якщо контакт видалив Delta Chat через помилки або небажану поведінку, будь ласка, розгляньте можливість написати повідомлення на нашому форумі підтримки щоб допомогти нам виявити та вирішити загальні проблеми. Дякуємо!
-Так, Delta Chat використовує безпечну підмножину OpenPGP і відображає індикатор безпеки у вигляді замка в повідомленні лише тоді, коли все повідомлення належним чином зашифровано і підписано. Наприклад, “Відокремлені підписи” не вважаються безпечними.
+Так, Delta Chat використовує безпечну підмножину OpenPGP яка вимагає, щоб все повідомлення було належним чином зашифровано і підписано. Наприклад, “відокремлені підписи” не вважаються безпечними.
OpenPGP сам по собі не є небезпечним. Більшість публічно обговорюваних проблем безпеки OpenPGP насправді виникають через недостатню зручність використання або погану реалізацію інструментів чи програм (або обох). Особливо важливо розрізняти OpenPGP, стандарт шифрування IETF, і GnuPG (GPG), інструмент командного рядка, що реалізує OpenPGP. @@ -771,19 +744,17 @@ Delta Chat скоріше використовує реалізацію OpenPGP
Delta Chat також ніколи не був вразливим до EFAIL-атаки “Пряма ексфільтрація” тому що він розшифровує лише “багатокомпонентні/зашифровані” повідомлення, які містять рівно одну зашифровану і підписану частину, як визначено специфікацією Autocrypt Level 1.
-Навіть якщо ваші повідомлення не гарантовано зашифровані наскрізним шифруванням, вони все одно захищені від інтернет-провайдерів, таких як мобільні або кабельні компанії. Однак, ваші провайдери та провайдери електронної пошти одержувача можуть читати, аналізувати або навіть змінювати ваші повідомлення, включаючи будь-які вкладення, якщо вони не зашифровані наскрізним шифруванням.
+Якщо ви надсилаєте або отримуєте електронні листи без наскрізного шифрування (використовуючи класичний сервер електронної пошти), вони все одно захищені від мобільних або кабельних компаній, які не можуть читати чи змінювати ваші повідомлення. Однак як ваш, так і поштовий провайдер одержувача можуть читати, аналізувати або змінювати ваші листи, включаючи будь-які вкладення.
За замовчуванням Delta Chat використовує суворе TLS-шифрування яке захищає з’єднання між вашим пристроєм і провайдером електронної пошти. Вся робота з TLS-шифруванням Delta Chat пройшла незалежний аудит безпеки. Крім того, з’єднання між вашим провайдером та провайдером електронної пошти одержувача зазвичай також шифрується при передачі даних. Якщо задіяні поштові сервери підтримують MTA-STS то між провайдерами електронної пошти буде застосовуватися транспортне шифрування в цьому випадку повідомлення Delta Chat ніколи не будуть доступні в Інтернеті у вигляді відкритого тексту навіть якщо повідомлення не було наскрізь зашифровано.
- -Зверніть увагу, що підтримка гарантованого наскрізного шифрування, на додаток до шифрування TLS, забезпечує повну безпеку між вашим пристроєм і пристроєм одержувача. Навіть ваш провайдер електронної пошти або інтернет-провайдер не зможуть прочитати або змінити ваші повідомлення.
Delta Chat захищає більшість метаданих повідомлень, поміщаючи наступну інформацію в наскрізно зашифровану частину повідомлень:
+На відміну від більшості інших месенджерів, додатки Delta Chat не зберігають жодних метаданих про контакти чи групи на серверах, навіть у зашифрованому вигляді. Натомість усі метадані груп наскрізно зашифровані та зберігаються виключно на пристроях користувачів.
+ +Тому поштові сервери можуть бачити лише
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
, Chat-Group-Member-Added
, Chat-Group-Member-Removed-Member-Added
.Secure-Join
, що містить команди безпечного приєднаннядату повідомлення,
+адреси відправника та одержувача
+і розмір повідомлення.
+Поштові сервери не мають доступу до цих захищених метаданих але вони бачать дату і розмір повідомлення, і, що важливіше, адреси відправника та отримувача. Поштовим серверам потрібні адреси одержувачів, щоб маршрутизувати і доставляти повідомлення на пристрої одержувача.
+Усі інші метадані повідомлень, контактів і груп містяться в наскрізно зашифрованій частині повідомлень.
Як для захисту від поштових серверів, що збирають метадані а також для захисту від загрози вилучення пристрою ми рекомендуємо використовувати chatmail-сервер для створення псевдонімних тимчасових профілів за допомогою сканування QR-коду. Зверніть увагу, що додатки Delta Chat на всіх платформах підтримують кілька профілів тому ви можете легко використовувати ситуативні профілі поруч з вашим “основним” профілем знаючи, що всі їхні дані, разом з усіма метаданими, будуть видалені. Більше того, якщо пристрій вилучено, то контакти, які використовують тимчасові профілі не можна буде легко ідентифікувати, на відміну від месенджерів, які розкривають номери телефонів у групах чату, які, в свою чергу, часто пов’язані з юридичними особами.
+Для захисту як від серверів електронної пошти, що збирають метадані, так і від загрози вилучення пристрою, ми рекомендуємо використовувати чатмейл-релей для створення чат-профілів із випадковими адресами електронної пошти для передавання повідомлень. Зверніть увагу, що додатки Delta Chat на всіх платформах підтримують кілька профілів, тому ви можете легко користуватися профілями, створеними для конкретних ситуацій, поруч із вашим «основним» профілем, з упевненістю, що всі їхні дані, включно з усіма метаданими, буде видалено. Більше того, у разі вилучення пристрою ідентифікувати чат-контакти, які використовують короткочасні профілі, буде вкрай складно.
-Ви можете перевірити стан наскрізного шифрування вручну в діалоговому вікні “Шифрування” (профіль користувача на Android/iOS або клацніть правою кнопкою миші на елементі списку чату користувача на робочому столі). Delta Chat показує там два відбитки. Якщо на вашому пристрої та пристрої вашого співрозмовника з’являються однакові відбитки, з’єднання безпечне.
- -Ні, поки ще ні.
-Маленький замок в бульбашці повідомлення позначає, що повідомлення було належним чином наскрізно зашифроване від відправника. Якщо немає замка, повідомлення не було належним чином наскрізно зашифровано, найімовірніше, тому що відправник використовує додаток або інтерфейс веб-пошти без підтримки кінцевого шифрування.
- -Месенджер Signal запровадив [“Запечатаного відправника” у 2018 році] (https://signal.org/blog/sealed-sender/) щоб їхня серверна інфраструктура не знала, хто надсилає повідомлення певній групі одержувачів. Це особливо важливо, оскільки сервер Signal знає номер мобільного телефону кожного акаунта, який зазвичай асоціюється з паспортними даними.
-Якщо контакт використовує поштову програму, яка не підтримує Autocrypt всі повідомлення за участю цього контакту (в групі або чаті 1:1) не будуть наскрізно зашифровані, а отже, не показуватимуть “висячого замка” з повідомленнями. Зверніть увагу, що навіть якщо ваші контакти використовують Delta Chat у своєму акаунті, вони також можуть використовувати програму електронної пошти без функції шифрування, що може спричинити періодичні незашифровані повідомлення. Відповідати незашифрованими на незашифровані повідомлення вимагає Autocrypt щоб запобігти отриманню нечитабельних повідомлень на стороні ваших контактів та їхніх поштових програм, які не підтримують Autocrypt.
- -Якщо вам потрібен безпечний наскрізно зашифрований чат з контактом який використовує свій акаунт як у Delta Chat, так і в інших додатках (наприклад, веб-пошті), що не підтримують автошифрування, найкраще налаштувати гарантоване наскрізне шифрування з ними, а потім створити груповий чат з гарантованим наскрізним шифруванням, учасниками якого будете ви двоє. У цьому груповому чаті всі повідомлення будуть наскрізно зашифровані навіть якщо в прямому чаті між вами буде “… надіслано повідомлення з іншого пристрою”.
- -Найкращий спосіб забезпечити наскрізне шифрування кожного повідомлення, а метадані видалялися якнайшвидше, це використання чатів з гарантованим наскрізним шифруванням -та увімкнення зникаючих повідомлень.
- -Гарантований наскрізно шифрований чат захищає від MITM-атак, а увімкнення функції зникнення повідомлень видаляє повідомлення на сервері через певний час, налаштований користувачем.
- -Якщо вам не потрібне більш довготривале зберігання копій ваших повідомлень на сервері, ви також можете увімкнути “автоматично видаляти повідомлення з сервера”.
+Навіть якщо чат-мейл релей не запитує ніяких приватних даних (в тому числі номерів телефонів), все одно може мати сенс захистити реляційні метадані між адресами. Ми не передбачаємо великих проблем у використанні випадкових одноразових адрес електронної пошти для запечатаних відправлень але реалізація такої можливості ще не є пріоритетною.
Ні, Delta Chat не підтримує ідеальну пряму секретність (PFS). Це означає, що якщо ваш приватний ключ дешифрування Delta Chat витік, і хтось зібрав ваші попередні транзитні повідомлення, він зможе розшифрувати і прочитати їх за допомогою витоку ключа розшифрування.
+Ні, поки ще ні.
-Зауважте, однак, що якщо хтось отримає ваші ключі розшифрування, вони, як правило, також зможуть отримати ваші повідомлення, незалежно від того, чи працює Perfect Forward Secrecy чи ні. Типовою реальною ситуацією для витоку ключів дешифрування є вилучення пристрою яку ми обговорюємо в нашій відповіді про метадані та вилучення пристрою.
+Delta Chat наразі не підтримує ідеальну пряму секретність (Perfect Forward Secrecy, PFS). Це означає, що якщо ваш приватний ключ для розшифрування буде скомпрометовано, а хтось заздалегідь зібрав ваші повідомлення під час передачі, він зможе розшифрувати та прочитати їх, використовуючи зламаний ключ. Зверніть увагу, що пряма секретність підвищує рівень безпеки лише в тому разі, якщо ви видаляєте повідомлення. Інакше, якщо хтось отримує доступ до ваших ключів розшифрування, він зазвичай також має доступ до всіх ваших невидалених повідомлень і навіть не потребує розшифровувати заздалегідь перехоплені дані.
-Можливо, що Delta Chat розвивається для підтримки Perfect Forward Secrecy, тому що OpenPGP - це лише контейнер для зашифрованих повідомлень, але керування ключами шифрування (і, відповідно, ротація ключів або “храповик” ключів) може бути організоване у гнучкий спосіб. Дивіться Прототип PFS від Seqouia щодо існуючих експериментів у спільноті реалізаторів OpenPGP.
+Ми розробили підхід Forward Secrecy, який витримав початкову експертизу від деяких криптографів та експертів з реалізації але чекає на більш офіційний звіт щоб переконатися, що він надійно працює в об’єднаних системах обміну повідомленнями та при використанні декількох пристроїв, перш ніж його можна буде реалізувати в ядрі чату, що зробить його доступним у всіх клієнтах чату.
-Це залежить від того, що для вас важливо. Delta Chat не підтримує PFS, як Signal але він забезпечує гарантовано наскрізні зашифровані чати які захищені від скомпрометованих серверів або пошкоджених мереж. Signal та більшість інших месенджерів, що підтримують PFS, не надають практичної схеми захисту чат-груп від мережевих атак які, можливо, викликають більше занепокоєння ніж потенційний зловмисник, який заволодіє вашим телефоном і приватними налаштуваннями шифрування, але чомусь не ваші повідомлення, але має повний запис усіх минулих зашифрованих повідомлень.
+Ні, поки ще ні.
-У будь-якому випадку, наскрізне шифрування Delta Chat використовує безпечну підмножину OpenPGP який пройшов незалежний аудит безпеки.
+Delta Chat використовує бібліотеку Rust OpenPGP rPGP яка підтримує останню версію IETF Post-Quantum-Cryptography OpenPGP draft. Ми плануємо додати підтримку PQC у chatmail core після того, як проект буде завершено у IETF у співпраці з іншими розробниками OpenPGP.
+ +Ви можете перевірити стан наскрізного шифрування вручну в діалоговому вікні “Шифрування” (профіль користувача на Android/iOS або клацніть правою кнопкою миші на елементі списку чату користувача на робочому столі). Delta Chat показує там два відбитки. Якщо на вашому пристрої та пристрої вашого співрозмовника з’являються однакові відбитки, з’єднання безпечне.
За допомогою списку розсилки ви можете надіслати повідомлення одразу багатьом одержувачам; +одержувачі не можуть відповідати у цьому списку. +Списки розсилки все ще дуже експериментальні і, ймовірно, будуть замінені чимось іншим, слідкуйте за новинами :)
Примітка: +Зміна адреси електронної пошти тимчасово відключена +через постійні зміни в ядрі DeltaChat. +Ця функція буде знову доступна через кілька місяців.
+Змініть свою адресу в розділі “Налаштування → Додатково → Пароль та обліковий запис” та введіть пароль вашого нового поштового акаунта (і, за необхідності, налаштування сервера). Ви отримаєте інформаційне повідомлення про те, що ви переїжджаєте на нову адресу. Додаткове повідомлення також з’явиться у вашому чаті “Повідомлення пристрою”.
@@ -1309,17 +1256,17 @@ Delta Chat скоріше використовує реалізацію OpenPGP Проте для коректної роботи деяких провайдерів потрібні специфічні налаштування. Дивіться наш огляд провайдерівAutocrypt 用于自动
-与联系人和群组聊天建立端到端加密。
-Autocrypt 使用 OpenPGP 标准的有限且安全子集。
-端到端加密消息标有挂锁
-。
Delta Chat uses a secure subset of the OpenPGP standard +to provide automatic end-to-end encryption using these protocols:
-安全加入协议
-用于建立具有保证的端到端加密的聊天,
-从而防止网络攻击和受损服务器。
-标有绿色复选标记的聊天
-
-保证端到端加密消息。
Secure-Join +to exchange encryption setup information through QR-code scanning or “invite links”.
+Autocrypt is used for automatically +establishing end-to-end encryption between contacts and all members of a group chat.
+Sharing a contact to a +chat +enables receivers to use end-to-end encryption with the contact.
+Delta Chat does not query, publish or interact with any OpenPGP key servers.
所有端到端加密的消息都带有挂锁:
- -如果聊天标题旁边有绿色复选标记,则保证端到端加密:
- -All messages in Delta Chat are end-to-end encrypted by default. +Since the Delta Chat Version 2 release series (July 2025) +there are no lock or similar markers on end-to-end encrypted messages, anymore.
-如果你与你的聊天伙伴有第二个通信渠道, -例如视频聊天或不同的即时通讯应用, -你可以生成邀请链接。
+If you use default chatmail relays, +it is impossible to receive or send messages without end-to-end encryption.
-如果你们面对面在一起, -你可以向你的聊天伙伴展示二维码。
+If you instead create a profile using a classic e-mail server,
+you can send and receive messages without end-to-end encryption.
+Such messages lacking end-to-end encryption are marked with an e-mail icon
+.
You can send an invite link through another private chat, +show an invitation QR code when next to each other or in a video call, +or click on a “contact” that was shared in a chat.
对于直接 1:1 聊天邀请,
-点击 Delta Chat 应用主屏幕上的二维码图标 。
For direct 1:1 chat invitations,
+tap the QR Code icon
+on the Delta Chat app main screen.
让你的聊天伙伴用他们的 Delta Chat 应用扫描二维码图像, -或点击“复制”或“分享”以创建邀请链接 -并与你的聊天伙伴分享。
+Ask your chat partner to scan the QR image +with their Delta Chat app, +or click “Copy” or “Share” to create an invite link +and share it with your chat partner.
-现在等待 安全加入网络消息在两个设备之间交换。
+Now wait while end-to-end encryption is getting established.
如果两个设备都处于在线状态,
-双方最终都会看到一个(群组或直接)聊天,标题旁边带有绿色复选标记
-。
If both sides are online, they will soon see a (group or direct) chat +and can start messaging securely.
如果其中一个设备处于离线状态,则只有当设备再次连接互联网且安全加入网络协议完成时,绿色复选标记才会出现。
+If one side is offline or in bad network, +the ability to chat is delayed until connectivity is restored.
恭喜!
-从现在开始您将会自动使用安全的端到端加密与此联系人联系,并且双方都可以将对方添加到绿色复选标记的群组
-,从而自动在其成员之间传播有保障的端到端加密。
Congratulations! +You now will automatically use end-to-end encryption +with this contact. +If you add each other to chat groups, +end-to-end encryption will be established among all members.
带有绿色复选标记的聊天标题
-
-表示聊天中的所有消息都将进行端到端加密,
-并且不会被受损的电子邮件服务器或互联网提供商读取或更改。
-加入带有绿色复选标记的群组聊天
-可以安全地传播每个人的加密信息(和绿色复选标记),
-从而保证群组和成员之间的端到端加密。
带有绿色复选标记的联系人配置文件
-
-表示当前保证与联系人的消息传递是端到端加密的。
-每个带有绿色复选标记的联系人要么直接与你进行了 二维码扫描,
-要么由另一个带有绿色复选标记的联系人介绍。
-当向群组添加成员时,介绍会自动发生。
-任何将联系人添加到带有绿色复选标记的群组的人都成为
-那些还不认识添加的联系人的成员的介绍人。
-在联系人配置文件中,你可以反复点击“由…介绍”文本
-,直到你到达直接与你进行 二维码扫描 的那个人。
请注意,在联系人配置文件中,你可能会看到并点击介绍人,
但在配置文件标题中没有绿色复选标记。
这通常意味着联系人“从另一台设备发送了消息”。
A contact profile might show a green checkmark
+
+and an “Introduced by” line.
+Every green-checkmarked contact either did a direct QR-scan with you
+or was introduced by a another green-checkmarked contact.
+Introductions happen automatically when adding members to groups.
+Whoever adds a green-checkmarked contact to a group with only green-checkmarked members
+becomes an introducer.
+In a contact profile you can tap on the “Introduced by …” text repeatedly
+until you get to the one with whom you directly did a QR-scan.
有关“保证的端到端加密”的更深入讨论, 请参阅 安全加入协议, 并专门阅读有关“已验证群组”的内容,这是 此处所谓的“带有绿色复选标记”或“保证的端到端加密”聊天的技术术语。
-你与联系人的聊天失去了保证的端到端加密。 -当你看到此警告时,此聊天的绿色复选标记和联系人已被删除。 -如果你发现保证的端到端加密突然下降 -对于此联系人来说很意外,请不要接受警告! -相反,请通过第二个渠道( -如视频通话、其他即时通讯应用或电话)与你的联系人核实 -,以找出发生了什么。
- -如果你的联系人实际上导致了保证的端到端加密下降, -请参阅以下段落,了解常见原因及其缓解措施。 -无论如何,所有其他带有绿色复选标记的聊天都保持保证的端到端加密, -即使该联系人是那里的成员。
- -你的联系人在第二台设备(手机或笔记本电脑)上使用 Delta Chat
- -如果他们有另一台运行 Delta Chat 应用的设备, -他们应该从新设备中删除配置文件, -并按照此处所述将其添加为第二台设备。 -在他们之后给你发消息后,警告将消失, -并且保证的加密将在你的联系人的两台设备之间建立。
- -你的联系人使用他们的旧帐户登录名重新安装了 Delta Chat
- -如果他们有备份文件, -他们应该从新设备中删除配置文件, -而是导入备份文件以重新创建他们的配置文件。 -在他们之后给你发消息后,警告将消失, -并且保证的加密将为此联系人重新建立。
- -如果他们没有备份文件,最好与你的聊天伙伴执行 二维码扫描, -以重新建立保证的端到端加密。
- -你的联系人通过 Webmail 界面或其他电子邮件应用发送了邮件, -并且将很快恢复使用 Delta Chat。
- -如果你确定联系人有时使用 Webmail, -或其他缺少端到端加密的邮件应用, -那么你可以接受警告。 -一旦你的联系人再次使用 Delta Chat, -保证的端到端加密将自动重新建立。
- -你的联系人完全停止使用 Delta Chat
- -有时保持联系比端到端加密更重要。 -“传输层加密” (TLS) 可能仍然有意义地保护 -你的设备和电子邮件服务器之间消息的机密性。 -但是,如果没有端到端加密,你和你的联系人将信任你的电子邮件服务器 -不会读取或操纵你的消息,也不会将其交给第三方。
- -在任何情况下,你都无法做太多其他事情,只能接受警告。 -另请从任何活动的带有绿色复选标记的群组中删除该联系人, -你可以在联系人配置文件中的“共享聊天”中找到这些群组。 -这可以避免你的联系人收到“无法读取”的消息。
- -如果联系人因为错误或不良行为而删除了 Delta Chat, -请考虑发布到我们的 支持论坛, -以帮助我们识别和解决常见问题。 谢谢!
-是的,Delta Chat 使用 OpenPGP 的安全子集, -并且仅在消息上显示挂锁安全指示器 -,前提是整个消息都已正确加密和签名。 -例如,“分离签名”不被视为安全。
+Yes, Delta Chat uses a secure subset of OpenPGP +requiring the whole message to be properly encrypted and signed. +For example, “Detached signatures” are not treated as secure.
OpenPGP 加密标准本身不存在安全隐患。 目前公众讨论中涉及的 OpenPGP 安全问题, @@ -923,7 +864,7 @@ Delta Chat 实际使用的是 Rust 语言编写的 OpenPGP 实现库 - 你们是否考虑过使用 OpenPGP 的替代方案进行端到端加密? + Did you consider using alternatives to OpenPGP for end-to-end-encryption? @@ -965,17 +906,15 @@ Delta Chat 实际使用的是 Rust 语言编写的 OpenPGP 实现库 - 如果端到端加密不可用,消息是否会以明文形式暴露? + Are messages marked with the mail icon exposed on the Internet? -
即使你的消息未保证端到端加密, -它们仍然受到互联网提供商(如手机或有线电视公司)的保护。 -但是,你的和你的接收者的电子邮件提供商 -可能会读取、分析甚至修改你的消息, -包括任何附件, -如果它们未进行端到端加密。
+If you are sending or receiving e-mail messages without end-to-end encryption (using a classic e-mail server), +they are still protected from cell or cable companies who can not read or modify your e-mail messages. +But both your and your recipient’s e-mail providers +may read, analyze or modify your messages, including any attachments.
Delta Chat 默认使用严格的 TLS 加密, @@ -986,10 +925,6 @@ Delta Chat 的所有 TLS 处理都经过了独立的 如果所涉及的电子邮件服务器支持 MTA-STS, 则将在电子邮件提供商之间强制执行传输加密, 在这种情况下,即使消息未进行端到端加密,Delta Chat 通信也永远不会以明文形式暴露给互联网。
- -请注意,在 TLS 加密之上保持保证的端到端加密 -可在你的和接收者的设备之间提供普遍的安全性。 -即使你的电子邮件或互联网提供商也无法读取或修改你的消息。
Delta Chat 通过将以下信息放入消息的端到端加密部分来保护大多数消息元数据:
+Unlike most other messengers, +Delta Chat apps do not store any metadata about contacts or groups on servers, also not in encrypted form. +Instead, all group metadata is end-to-end encrypted and stored on end-user devices, only.
+ +E-mail Servers can therefore only see
Chat-Disposition-Notification-To
)Ephemeral-Timer
)Chat-Group-Member-Removed
, Chat-Group-Member-Added
Secure-Join
标头the message date,
+sender and receiver addresses
+and message size.
+电子邮件服务器无法访问此受保护的元数据, -但它们可以看到消息日期以及消息大小, -更重要的是,可以看到发件人和收件人地址。 -电子邮件服务器需要收件人地址来路由和 -将消息传递到接收者的设备。
+All other message, contact and group metadata resides in the end-to-end encrypted part of messages.
为了防止收集元数据的电子邮件服务器 -以及设备查封的威胁, -我们建议使用 Chatmail 服务器 -通过二维码扫描创建匿名临时配置文件。 -请注意,所有平台上的 Delta Chat 应用都支持多配置文件, -因此你可以轻松地在你“主要”配置文件旁边使用特定于情况的配置文件, -并且知道它们的所有数据以及所有元数据都将被删除。 -此外,如果设备被查封,则与使用临时配置文件的联系人 -相比,无法轻易识别,因为即时通讯应用会在聊天群组中显示 -电话号码,而电话号码通常与合法身份相关联。
+Both for protecting against metadata-collecting e-mail servers +as well as against the threat of device seizure +we recommend to use a chatmail relay +to create chat profiles using random e-mail addresses for transport. +Note that Delta Chat apps on all platforms support multiple profiles +so you can easily use situation-specific profiles next to your “main” profile +with the knowledge that all their data, along with all metadata, will be deleted. +Moreover, if a device is seized then chat contacts using short-lived profiles +can not be identified easily.
-你可以在“加密”对话框中手动检查端到端加密状态 -(Android/iOS 上的用户配置文件或桌面上的用户聊天列表项上右键单击)。 -Delta Chat 在此处显示两个指纹。 -如果相同的指纹出现在你自己的设备和你联系人的设备上, -则连接是安全的。
- -No, not yet.
-消息气泡中的小挂锁表示 -消息已从给定的发件人正确进行端到端加密。 -如果没有挂锁,则消息未正确进行端到端加密, -最可能是因为发件人使用的应用或 Webmail 界面 -不支持端到端加密。
- -The Signal messenger introduced “Sealed Sender” in 2018 +to keep their server infrastructure ignorant of who is sending a message to a set of recipients. +It is particularly important because the Signal server knows the mobile number of each account, +which is usually associated with a passport identity.
-如果联系人使用非 Autocrypt 电子邮件应用, -则涉及此联系人(在群组或 1:1 聊天中)的所有消息 -将不会进行端到端加密,因此消息中不会显示“挂锁”。 -请注意,即使你的联系人在其帐户上使用 Delta Chat, -他们也可能在该帐户上使用非 Autocrypt 电子邮件应用, -这可能会导致间歇性未加密的消息。 -回复未加密的消息是 Autocrypt 强制执行的 -,以防止你的联系人及其非 Autocrypt 电子邮件应用端出现无法读取的消息。
- -如果你需要与 -同时使用 Delta Chat 和非 Autocrypt 应用(例如 Webmail)的电子邮件帐户的联系人进行安全端到端加密的聊天, -最好与他们设置 保证的端到端加密, -然后创建一个由你二人作为成员的保证的端到端加密的群组聊天。 -在此群组聊天中,所有消息都将进行端到端加密, -即使你二人之间的直接聊天有 -“…从另一台设备发送了消息” 警告
- -确保每条消息都进行端到端加密, -并尽快删除元数据的最佳方法是 -使用具有保证的端到端加密的聊天 -并开启 阅后即焚消息。
- -保证的端到端加密聊天可防止 MITM 攻击, -而开启阅后即焚消息会在用户配置的时间后删除服务器上的消息。
- -如果你不需要在服务器上保留消息的长期副本, -你还可以开启 “自动从服务器删除消息”。
+Even if chatmail relays +do not ask for any private data (including no phone numbers), +it might still be worthwhile to protect relational metadata between addresses. +We don’t foresee bigger problems in using random throw-away e-mail addresses for sealed sending +but an implementation has not been agreed as a priority yet.
不,Delta Chat 不支持完美前向保密 (PFS)。 -这意味着,如果您的 Delta Chat 私人解密密钥泄露, -并且有人收集了您之前传输的消息, -他们将能够使用泄露的解密密钥解密并阅读这些消息。
+No, not yet.
-但请注意,如果有人获得您的解密密钥, -他们通常也能够获得您的消息, -无论是否实施了完全前向保密。 -泄露解密密钥的典型现实情况是设备扣押, -我们在关于元数据和设备扣押的回答中讨论了这一点。
+Delta Chat today doesn’t support Perfect Forward Secrecy (PFS). +This means that if your private decryption key is leaked, +and someone has collected your prior in-transit messages, +they will be able to decrypt and read them using the leaked decryption key. +Note that Forward Secrecy only increases security if you delete messages. +Otherwise, someone obtaining your decryption keys +is typically also able to get all your non-deleted messages +and doesn’t even need to decrypt any previously collected messages.
-Delta Chat 可能会发展为支持完美前向保密, -因为 OpenPGP 只是加密消息的容器, -但密钥管理(以及密钥轮换或密钥“棘轮”) -可以以灵活的方式组织。 -请参阅 Seqouia 的 PFS 原型, -了解 OpenPGP 实现者社区中现有的实验。
+We designed a Forward Secrecy approach that withstood +initial examination from some cryptographers and implementation experts +but is pending a more formal write up +to ascertain it reliably works in federated messaging and with multi-device usage, +before it could be implemented in chatmail core, +which would make it available in all chatmail clients.
-这取决于对你而言重要的是什么。 -Delta Chat 不支持像 Signal 那样的 PFS, -但它提供了 保证的端到端加密聊天, -可以安全地抵御受损的服务器或损坏的网络。 -Signal 和大多数其他支持 PFS 的即时通讯应用 -没有提供实用的方案来保护聊天群组免受网络攻击, -而网络攻击可以说比 -潜在的攻击者查封你的手机和私有加密设置 -但不知何故没有你的消息,却完整记录了所有 -过去的加密消息更令人担忧。
+No, not yet.
-在任何情况下,Delta Chat 的端到端加密都使用 OpenPGP 的安全子集, -该子集已 通过独立的安全审计。
+Delta Chat uses the Rust OpenPGP library rPGP +which supports the latest IETF Post-Quantum-Cryptography OpenPGP draft. +We aim to add PQC support in chatmail core after the draft is finalized at the IETF +in collaboration with other OpenPGP implementers.
+ +你可以在“加密”对话框中手动检查端到端加密状态 +(Android/iOS 上的用户配置文件或桌面上的用户聊天列表项上右键单击)。 +Delta Chat 在此处显示两个指纹。 +如果相同的指纹出现在你自己的设备和你联系人的设备上, +则连接是安全的。
With a Broadcast List you can send a message to many recipients at once; +the recipients cannot reply in that list. +Broadcast lists are still highly experimental +and will very probably be replaced by something else, stay tuned :)
Note: +Changing email addresses is temporarily disabled +because of ongoing changes to the DeltaChat core. +It should be available again in a few months.
+
+ * A few releases after the PGP-contacts migration (which happened in 2025-05),
+ * we can remove this function again.
+ */
+ public static void maybeShowMigrationError(Context context) {
+ try {
+ String lastError = DcHelper.getRpc(context).getMigrationError(DcHelper.getContext(context).getAccountId());
+
+ if (lastError != null && !lastError.isEmpty()) {
+ Log.w(TAG, "Opening account failed, trying to share error: " + lastError);
+
+ String subject = "Delta Chat failed to update";
+ String email = "delta@merlinux.eu";
+
+ new AlertDialog.Builder(context)
+ .setMessage(context.getString(R.string.error_x, lastError))
+ .setNeutralButton(R.string.global_menu_edit_copy_desktop, (d, which) -> {
+ Util.writeTextToClipboard(context, lastError);
+ })
+ .setPositiveButton(R.string.menu_send, (d, which) -> {
+ Intent sharingIntent = new Intent(
+ Intent.ACTION_SENDTO, Uri.fromParts(
+ "mailto", email, null
+ )
+ );
+ sharingIntent.putExtra(Intent.EXTRA_EMAIL, new String[]{email});
+ sharingIntent.putExtra(Intent.EXTRA_SUBJECT, subject);
+ sharingIntent.putExtra(Intent.EXTRA_TEXT, lastError);
+
+ if (sharingIntent.resolveActivity(context.getPackageManager()) == null) {
+ Log.w(TAG, "No email client found to send crash report");
+ sharingIntent = new Intent(Intent.ACTION_SEND);
+ sharingIntent.setType("text/plain");
+ sharingIntent.putExtra(Intent.EXTRA_SUBJECT, subject);
+ sharingIntent.putExtra(Intent.EXTRA_TEXT, lastError);
+ sharingIntent.putExtra(Intent.EXTRA_EMAIL, email);
+ }
+
+ Intent chooser =
+ Intent.createChooser(sharingIntent, "Send using...");
+ chooser.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+ chooser.addFlags(Intent.FLAG_ACTIVITY_MULTIPLE_TASK);
+
+ context.startActivity(chooser);
+ })
+ .setCancelable(false)
+ .show();
+ }
+ } catch (RpcException e) {
+ e.printStackTrace();
+ }
+ }
}
diff --git a/src/main/java/org/thoughtcrime/securesms/connect/DirectShareUtil.java b/src/main/java/org/thoughtcrime/securesms/connect/DirectShareUtil.java
index 64657aed9..a9343226b 100644
--- a/src/main/java/org/thoughtcrime/securesms/connect/DirectShareUtil.java
+++ b/src/main/java/org/thoughtcrime/securesms/connect/DirectShareUtil.java
@@ -128,7 +128,7 @@ public class DirectShareUtil {
Recipient recipient = new Recipient(context, chat);
Bitmap avatar = getIconForShortcut(context, recipient);
- results.add(new ShortcutInfoCompat.Builder(context, Integer.toString(chat.getId()))
+ results.add(new ShortcutInfoCompat.Builder(context, "chat-" + dcContext.getAccountId() + "-" + chat.getId())
.setShortLabel(chat.getName())
.setLongLived(true)
.setRank(i+1)
diff --git a/src/main/java/org/thoughtcrime/securesms/contacts/ContactSelectionListAdapter.java b/src/main/java/org/thoughtcrime/securesms/contacts/ContactSelectionListAdapter.java
index 56cd0e765..300afece7 100644
--- a/src/main/java/org/thoughtcrime/securesms/contacts/ContactSelectionListAdapter.java
+++ b/src/main/java/org/thoughtcrime/securesms/contacts/ContactSelectionListAdapter.java
@@ -268,8 +268,10 @@ public class ContactSelectionListAdapter extends RecyclerView.Adapter> someGrantedListener;
- private Consumer
> someDeniedListener;
- private Consumer
> somePermanentlyDeniedListener;
-
private @DrawableRes int[] rationalDialogHeader;
private String rationaleDialogMessage;
@@ -148,29 +142,13 @@ public class Permissions {
return this;
}
- public PermissionsBuilder onSomeGranted(Consumer
> someGrantedListener) {
- this.someGrantedListener = someGrantedListener;
- return this;
- }
-
- public PermissionsBuilder onSomeDenied(Consumer
> someDeniedListener) {
- this.someDeniedListener = someDeniedListener;
- return this;
- }
-
- public PermissionsBuilder onSomePermanentlyDenied(Consumer
> somePermanentlyDeniedListener) {
- this.somePermanentlyDeniedListener = somePermanentlyDeniedListener;
- return this;
- }
-
public void execute() {
if (alwaysGranted) {
allGrantedListener.run();
return;
}
- PermissionsRequest request = new PermissionsRequest(allGrantedListener, anyDeniedListener, anyPermanentlyDeniedListener, anyResultListener,
- someGrantedListener, someDeniedListener, somePermanentlyDeniedListener);
+ PermissionsRequest request = new PermissionsRequest(allGrantedListener, anyDeniedListener, anyPermanentlyDeniedListener, anyResultListener);
if (ifNecesary && (permissionObject.hasAll(requestedPermissions) || !condition)) {
executePreGrantedPermissionsRequest(request);
@@ -183,7 +161,7 @@ public class Permissions {
private void executePreGrantedPermissionsRequest(PermissionsRequest request) {
int[] grantResults = new int[requestedPermissions.length];
- for (int i=0;i
> someGrantedListener;
- private final @Nullable Consumer
> someDeniedListener;
- private final @Nullable Consumer
> somePermanentlyDeniedListener;
-
PermissionsRequest(@Nullable Runnable allGrantedListener,
@Nullable Runnable anyDeniedListener,
@Nullable Runnable anyPermanentlyDeniedListener,
- @Nullable Runnable anyResultListener,
- @Nullable Consumer
> someGrantedListener,
- @Nullable Consumer
> someDeniedListener,
- @Nullable Consumer
> somePermanentlyDeniedListener)
+ @Nullable Runnable anyResultListener)
{
this.allGrantedListener = allGrantedListener;
this.anyDeniedListener = anyDeniedListener;
this.anyPermanentlyDeniedListener = anyPermanentlyDeniedListener;
this.anyResultListener = anyResultListener;
-
- this.someGrantedListener = someGrantedListener;
- this.someDeniedListener = someDeniedListener;
- this.somePermanentlyDeniedListener = somePermanentlyDeniedListener;
}
void onResult(String[] permissions, int[] grantResults, boolean[] shouldShowRationaleDialog) {
@@ -56,9 +43,9 @@ class PermissionsRequest {
} else {
boolean preRequestShouldShowRationaleDialog = PRE_REQUEST_MAPPING.get(permissions[i]);
- if ((somePermanentlyDeniedListener != null || anyPermanentlyDeniedListener != null) &&
- !preRequestShouldShowRationaleDialog && !shouldShowRationaleDialog[i])
- {
+ if (anyPermanentlyDeniedListener != null
+ && !preRequestShouldShowRationaleDialog
+ && !shouldShowRationaleDialog[i]) {
permanentlyDenied.add(permissions[i]);
} else {
denied.add(permissions[i]);
@@ -68,18 +55,14 @@ class PermissionsRequest {
if (allGrantedListener != null && !granted.isEmpty() && (denied.isEmpty() && permanentlyDenied.isEmpty())) {
allGrantedListener.run();
- } else if (someGrantedListener != null && !granted.isEmpty()) {
- someGrantedListener.accept(granted);
}
if (!denied.isEmpty()) {
if (anyDeniedListener != null) anyDeniedListener.run();
- if (someDeniedListener != null) someDeniedListener.accept(denied);
}
if (!permanentlyDenied.isEmpty()) {
if (anyPermanentlyDeniedListener != null) anyPermanentlyDeniedListener.run();
- if (somePermanentlyDeniedListener != null) somePermanentlyDeniedListener.accept(permanentlyDenied);
}
if (anyResultListener != null) {
diff --git a/src/main/java/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java b/src/main/java/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java
index a41f302ed..63d980aa1 100644
--- a/src/main/java/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java
+++ b/src/main/java/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java
@@ -176,9 +176,8 @@ public class AdvancedPreferenceFragment extends ListSummaryPreferenceFragment
newBroadcastList.setOnPreferenceChangeListener((preference, newValue) -> {
if ((Boolean)newValue) {
new AlertDialog.Builder(requireActivity())
- .setTitle("Thanks for trying out \"Broadcast Lists\"!")
- .setMessage("• You can now create new \"Broadcast Lists\" from the \"New Chat\" dialog\n\n"
- + "• In case you are using more than one device, broadcast lists are currently not synced between them\n\n"
+ .setTitle("Thanks for trying out \"Channels\"!")
+ .setMessage("• You can now create new \"Channels\" from the \"New Chat\" dialog\n\n"
+ "• If you want to quit the experimental feature, you can disable it at \"Settings / Advanced\"")
.setCancelable(false)
.setPositiveButton(R.string.ok, null)
diff --git a/src/main/java/org/thoughtcrime/securesms/preferences/ChatBackgroundActivity.java b/src/main/java/org/thoughtcrime/securesms/preferences/ChatBackgroundActivity.java
index f4b58b581..b2d85c0d5 100644
--- a/src/main/java/org/thoughtcrime/securesms/preferences/ChatBackgroundActivity.java
+++ b/src/main/java/org/thoughtcrime/securesms/preferences/ChatBackgroundActivity.java
@@ -71,6 +71,7 @@ public class ChatBackgroundActivity extends PassphraseRequiredActionBarActivity
actionBar.setTitle(R.string.pref_background);
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setHomeAsUpIndicator(R.drawable.ic_close_white_24dp);
+ actionBar.setElevation(0); // TODO: use custom toolbar instead
}
}
diff --git a/src/main/java/org/thoughtcrime/securesms/profiles/AvatarHelper.java b/src/main/java/org/thoughtcrime/securesms/profiles/AvatarHelper.java
index 2ebe7afa7..bf98af3d4 100644
--- a/src/main/java/org/thoughtcrime/securesms/profiles/AvatarHelper.java
+++ b/src/main/java/org/thoughtcrime/securesms/profiles/AvatarHelper.java
@@ -20,6 +20,8 @@ import java.io.FileOutputStream;
import java.io.IOException;
public class AvatarHelper {
+ /* the maximum width/height an avatar should have */
+ public static final int AVATAR_SIZE = 640;
public static void setGroupAvatar(Context context, int chatId, Bitmap bitmap) {
DcContext dcContext = DcHelper.getContext(context);
@@ -30,7 +32,7 @@ public class AvatarHelper {
try {
File avatar = File.createTempFile("groupavatar", ".jpg", context.getCacheDir());
FileOutputStream out = new FileOutputStream(avatar);
- bitmap.compress(Bitmap.CompressFormat.JPEG, 85, out);
+ bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out);
out.close();
dcContext.setChatProfileImage(chatId, avatar.getPath()); // The avatar is copied to the blobs directory here...
//noinspection ResultOfMethodCallIgnored
diff --git a/src/main/java/org/thoughtcrime/securesms/profiles/ProfileMediaConstraints.java b/src/main/java/org/thoughtcrime/securesms/profiles/ProfileMediaConstraints.java
deleted file mode 100644
index 72da12bcf..000000000
--- a/src/main/java/org/thoughtcrime/securesms/profiles/ProfileMediaConstraints.java
+++ /dev/null
@@ -1,23 +0,0 @@
-package org.thoughtcrime.securesms.profiles;
-
-
-import android.content.Context;
-
-import org.thoughtcrime.securesms.mms.MediaConstraints;
-
-public class ProfileMediaConstraints extends MediaConstraints {
- @Override
- public int getImageMaxWidth(Context context) {
- return 640;
- }
-
- @Override
- public int getImageMaxHeight(Context context) {
- return 640;
- }
-
- @Override
- public int getImageMaxSize(Context context) {
- return 5 * 1024 * 1024;
- }
-}
diff --git a/src/main/java/org/thoughtcrime/securesms/proxy/ProxySettingsActivity.java b/src/main/java/org/thoughtcrime/securesms/proxy/ProxySettingsActivity.java
index 6a9e8b63c..e21fe2404 100644
--- a/src/main/java/org/thoughtcrime/securesms/proxy/ProxySettingsActivity.java
+++ b/src/main/java/org/thoughtcrime/securesms/proxy/ProxySettingsActivity.java
@@ -50,6 +50,7 @@ public class ProxySettingsActivity extends BaseActionBarActivity
if (actionBar != null) {
actionBar.setTitle(R.string.proxy_settings);
actionBar.setDisplayHomeAsUpEnabled(true);
+ actionBar.setElevation(0); // TODO: use custom toolbar instead
}
adapter = new ProxyListAdapter(this);
diff --git a/src/main/java/org/thoughtcrime/securesms/qr/BackupReceiverFragment.java b/src/main/java/org/thoughtcrime/securesms/qr/BackupReceiverFragment.java
index 1dfb677b4..9dc659633 100644
--- a/src/main/java/org/thoughtcrime/securesms/qr/BackupReceiverFragment.java
+++ b/src/main/java/org/thoughtcrime/securesms/qr/BackupReceiverFragment.java
@@ -80,6 +80,7 @@ public class BackupReceiverFragment extends Fragment implements DcEventCenter.Dc
Log.i(TAG,"DC_EVENT_IMEX_PROGRESS, " + permille);
if (permille == 0) {
+ DcHelper.maybeShowMigrationError(getTransferActivity());
getTransferActivity().setTransferError("Receiving Error");
} else if (permille < 1000) {
percent = permille/10;
diff --git a/src/main/java/org/thoughtcrime/securesms/qr/BackupTransferActivity.java b/src/main/java/org/thoughtcrime/securesms/qr/BackupTransferActivity.java
index 428b0ab33..6673c5999 100644
--- a/src/main/java/org/thoughtcrime/securesms/qr/BackupTransferActivity.java
+++ b/src/main/java/org/thoughtcrime/securesms/qr/BackupTransferActivity.java
@@ -73,11 +73,11 @@ public class BackupTransferActivity extends BaseActionBarActivity {
switch(transferMode) {
case SENDER_SHOW_QR:
- initFragment(android.R.id.content, new BackupProviderFragment(), icicle);
+ initFragment(R.id.backup_provider_fragment, new BackupProviderFragment(), icicle);
break;
case RECEIVER_SCAN_QR:
- initFragment(android.R.id.content, new BackupReceiverFragment(), icicle);
+ initFragment(R.id.backup_provider_fragment, new BackupReceiverFragment(), icicle);
break;
}
@@ -85,6 +85,7 @@ public class BackupTransferActivity extends BaseActionBarActivity {
supportActionBar.setDisplayHomeAsUpEnabled(true);
supportActionBar.setHomeAsUpIndicator(R.drawable.ic_close_white_24dp);
supportActionBar.setTitle(title);
+ supportActionBar.setElevation(0); // TODO: use custom toolbar instead
}
@Override
diff --git a/src/main/java/org/thoughtcrime/securesms/qr/RegistrationQrActivity.java b/src/main/java/org/thoughtcrime/securesms/qr/RegistrationQrActivity.java
index ba27ce4a1..20d76ace3 100644
--- a/src/main/java/org/thoughtcrime/securesms/qr/RegistrationQrActivity.java
+++ b/src/main/java/org/thoughtcrime/securesms/qr/RegistrationQrActivity.java
@@ -42,6 +42,7 @@ public class RegistrationQrActivity extends BaseActionBarActivity {
getSupportActionBar().setTitle(R.string.scan_invitation_code);
}
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
+ getSupportActionBar().setElevation(0); // TODO: use custom toolbar instead
barcodeScannerView = findViewById(R.id.zxing_barcode_scanner);
barcodeScannerView.setStatusText(getString(R.string.qrscan_hint) + "\n ");
diff --git a/src/main/java/org/thoughtcrime/securesms/scribbles/UriGlideRenderer.java b/src/main/java/org/thoughtcrime/securesms/scribbles/UriGlideRenderer.java
index 3aaf91267..b822122df 100644
--- a/src/main/java/org/thoughtcrime/securesms/scribbles/UriGlideRenderer.java
+++ b/src/main/java/org/thoughtcrime/securesms/scribbles/UriGlideRenderer.java
@@ -179,7 +179,7 @@ final class UriGlideRenderer implements Renderer {
.diskCacheStrategy(DiskCacheStrategy.NONE)
.override(width, height)
.centerInside()
- .load(decryptable ? new DecryptableStreamUriLoader.DecryptableUri(imageUri) : imageUri);
+ .load(decryptable && imageUri!=null ? new DecryptableStreamUriLoader.DecryptableUri(imageUri) : imageUri);
}
@Override
diff --git a/src/main/java/org/thoughtcrime/securesms/util/LongClickCopySpan.java b/src/main/java/org/thoughtcrime/securesms/util/LongClickCopySpan.java
index 6da6511cf..7f64ca54f 100644
--- a/src/main/java/org/thoughtcrime/securesms/util/LongClickCopySpan.java
+++ b/src/main/java/org/thoughtcrime/securesms/util/LongClickCopySpan.java
@@ -58,7 +58,12 @@ public class LongClickCopySpan extends ClickableSpan {
String addr = prepareUrl(url);
Activity activity = (Activity) widget.getContext();
DcContext dcContext = DcHelper.getContext(activity);
- DcContact contact = dcContext.getContact(dcContext.createContact(null, addr));
+
+ int contactId = dcContext.lookupContactIdByAddr(addr);
+ if (contactId == 0 && dcContext.mayBeValidAddr(addr)) {
+ contactId = dcContext.createContact(null, addr);
+ }
+ DcContact contact = dcContext.getContact(contactId);
if (contact.getId() != 0 && !contact.isBlocked() && dcContext.getChatIdByContactId(contact.getId()) != 0) {
openChat(activity, contact);
} else {
diff --git a/src/main/java/org/thoughtcrime/securesms/util/Prefs.java b/src/main/java/org/thoughtcrime/securesms/util/Prefs.java
index 12234829f..4df6b2deb 100644
--- a/src/main/java/org/thoughtcrime/securesms/util/Prefs.java
+++ b/src/main/java/org/thoughtcrime/securesms/util/Prefs.java
@@ -172,7 +172,7 @@ public class Prefs {
return getBooleanPreference(context, "pref_developer_mode_enabled", false);
}
- public static boolean isNewBroadcastListAvailable(Context context) {
+ public static boolean isNewBroadcastAvailable(Context context) {
return getBooleanPreference(context, "pref_new_broadcast_list", false);
}
diff --git a/src/main/java/org/thoughtcrime/securesms/util/SelectedContactsAdapter.java b/src/main/java/org/thoughtcrime/securesms/util/SelectedContactsAdapter.java
index a4c670533..887e07c80 100644
--- a/src/main/java/org/thoughtcrime/securesms/util/SelectedContactsAdapter.java
+++ b/src/main/java/org/thoughtcrime/securesms/util/SelectedContactsAdapter.java
@@ -36,17 +36,19 @@ public class SelectedContactsAdapter extends BaseAdapter {
@NonNull private final Context context;
@Nullable private ItemClickListener itemClickListener;
@NonNull private final List