diff --git a/file/sniffer.js b/file/sniffer.js
index 5ad1265..0d9bf13 100644
--- a/file/sniffer.js
+++ b/file/sniffer.js
@@ -26,7 +26,7 @@ const fileSignatures = {
   'application/pdf': [[0x25, 0x50, 0x44, 0x46, 0x2d]], // '%PDF-'
 
   // Archive formats:
-  'application/gzip': [[0x1F, 0x8B]],
+  'application/gzip': [[0x1F, 0x8B, 0x08]],
   'application/x-tar': [ // 'ustar'
     [0x75, 0x73, 0x74, 0x61, 0x72, 0x00, 0x30, 0x30],
     [0x75, 0x73, 0x74, 0x61, 0x72, 0x20, 0x20, 0x00],