diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/cmd/function/CreateThunkFunctionCmd.java b/Ghidra/Features/Base/src/main/java/ghidra/app/cmd/function/CreateThunkFunctionCmd.java
index ef3430330a..130da02064 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/cmd/function/CreateThunkFunctionCmd.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/cmd/function/CreateThunkFunctionCmd.java
@@ -796,6 +796,9 @@ public class CreateThunkFunctionCmd extends BackgroundCommand {
 		}
 		// check the parent varnode
 		Register register = program.getRegister(regVarnode);
+		if (register == null) {
+			return false;
+		}
 		Register parentRegister = register.getParentRegister();
 		if (parentRegister == null) {
 			return false;