Require all auth data to be parsed

duo-labs · Mar 31, 2022 · 27d7469 · 27d7469
1 parent ad90c8a
commit 27d7469
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/webauthn/helpers/parse_authenticator_data.py b/webauthn/helpers/parse_authenticator_data.py
@@ -73,4 +73,10 @@ def parse_authenticator_data(val: bytes) -> AuthenticatorData:
         pointer += len(extension_bytes)
         authenticator_data.extensions = extension_bytes
 
+    # We should have parsed all authenticator data by this point
+    if (len(val) > pointer):
+        raise InvalidAuthenticatorDataStructure(
+            "Leftover bytes detected while parsing authenticator data"
+        )
+
     return authenticator_data