Mishandling of comma during folding and unicode-encoding of email headers
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 2.3epss 0.6%
exploitation probability
0.6%top 52% of all CVEs
observed exploitation
nono source reports it
During an address list folding when a separating comma ends up on a folded line and that line is to be unicode-encoded then the separator itself is also unicode-encoded. Expected behavior is that the separating comma remains a plan comma. This can result in the address header being misinterpreted by some mail servers.
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Affected products
Python Software Foundation · CPythonReferences
https://github.com/python/cpython/commit/09fab93c3d857496c0bd162797fab816c311ee48https://github.com/python/cpython/commit/70754d21c288535e86070ca7a6e90dcb670b8593https://github.com/python/cpython/commit/9148b77e0af91cdacaa7fe3dfac09635c3fe9a74https://github.com/python/cpython/commit/a4ef689ce670684ec132204b1cd03720c8e0a03dhttps://github.com/python/cpython/commit/d4df3c55e4c5513947f907f24766b34d2ae8c090https://github.com/python/cpython/issues/100884https://github.com/python/cpython/pull/100885https://github.com/python/cpython/pull/119099https://lists.debian.org/debian-lts-announce/2025/03/msg00013.htmlhttps://mail.python.org/archives/list/security-announce@python.org/thread/MB62IZMEC3UM6SGHP5LET5JX2Y7H4ZUR/