[3.8] bpo-33972: Fix EmailMessage.iter_attachments raising AttributeError (GH-14119) (GH-14380)
When certain malformed messages have content-type set to 'mulitpart/*' but
still have a single part body, iter_attachments can raise AttributeError. This
patch fixes it by returning a None value instead when the body is single part.
(cherry picked from commit 02257012f6d3821d816cb6a7e8461a88a05b9a08)
Co-authored-by: Abhilash Raj <maxking@users.noreply.github.com>
https://bugs.python.org/issue33972
diff --git a/Lib/email/message.py b/Lib/email/message.py
index b6512f2..1262602 100644
--- a/Lib/email/message.py
+++ b/Lib/email/message.py
@@ -1041,7 +1041,16 @@
maintype, subtype = self.get_content_type().split('/')
if maintype != 'multipart' or subtype == 'alternative':
return
- parts = self.get_payload().copy()
+ payload = self.get_payload()
+ # Certain malformed messages can have content type set to `multipart/*`
+ # but still have single part body, in which case payload.copy() can
+ # fail with AttributeError.
+ try:
+ parts = payload.copy()
+ except AttributeError:
+ # payload is not a list, it is most probably a string.
+ return
+
if maintype == 'multipart' and subtype == 'related':
# For related, we treat everything but the root as an attachment.
# The root may be indicated by 'start'; if there's no start or we