cpython/Misc/NEWS.d/next/Library/2019-05-27-15-29-46.bpo-30835.3FoaWH.rst

Fixed a bug in email parsing where a message with invalid bytes in
content-transfer-encoding of a multipart message can cause an AttributeError.
Patch by Andrew Donnellan.
bpo-30835: email: Fix AttributeError when parsing invalid CTE (GH-13598) * bpo-30835: email: Fix AttributeError when parsing invalid Content-Transfer-Encoding Parsing an email containing a multipart Content-Type, along with a Content-Transfer-Encoding containing an invalid (non-ASCII-decodable) byte will fail. email.feedparser.FeedParser._parsegen() gets the header and attempts to convert it to lowercase before comparing it with the accepted encodings, but as the header contains an invalid byte, it's returned as a Header object rather than a str. Cast the Content-Transfer-Encoding header to a str to avoid this. Found using the AFL fuzzer. Reported-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Andrew Donnellan <andrew@donnellan.id.au> * Add email and NEWS entry for the bugfix. 2019-06-05 02:00:47 +08:00			`Fixed a bug in email parsing where a message with invalid bytes in`
			`content-transfer-encoding of a multipart message can cause an AttributeError.`
			`Patch by Andrew Donnellan.`