The poplib module, when passed a user-controlled command, can have additional commands injected using newlines. Mitigation rejects commands containing control characters.CreditsOmar M. HasanReferenceshttps://github.com/python/cpython/pull/143924https://github.com/python/cpython/issues/143923https://mail.python.org/archives/list/security-announce@python.org/thread/CBFBOWVGGUJFSGITQCCBZS4GEYYZ7ZNE/https://github.com/python/cpython/commit/b234a2b67539f787e191d2ef19a7cbdce32874e7
