27988: Make sure iter_attachments does not mutate the payload list.
diff --git a/Lib/email/message.py b/Lib/email/message.py
index aefaf57..6cd6cb7 100644
--- a/Lib/email/message.py
+++ b/Lib/email/message.py
@@ -1022,7 +1022,7 @@
maintype, subtype = self.get_content_type().split('/')
if maintype != 'multipart' or subtype == 'alternative':
return
- parts = self.get_payload()
+ parts = self.get_payload().copy()
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