{"id":"CVE-2021-40347","aliases":["GHSA-v83x-78q3-gr2j","PYSEC-2021-319"],"url":"https://o3.security/vulnerability/CVE-2021-40347","summary":"GNU Mailman Postorius Access Control Issues","details":"An issue was discovered in views/list.py in GNU Mailman Postorius before 1.3.5. An attacker (logged into any account) can send a crafted POST request to unsubscribe any user from a mailing list, also revealing whether that address was subscribed in the first place.","published":"2021-09-10T19:15:08.163Z","modified":"2026-07-08T23:58:03.568247Z","cvss":{"score":5.4,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":2,"affectedPackages":[{"ecosystem":"PyPI","name":"postorius","fixedVersion":"1.3.5"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=993746"},{"type":"ADVISORY","url":"https://gitlab.com/mailman/postorius/-/tags"},{"type":"ADVISORY","url":"https://www.debian.org/security/2021/dsa-4970"},{"type":"FIX","url":"https://gitlab.com/mailman/postorius/-/commit/3d880c56b58bc26b32eac0799407d74b64b7474b"},{"type":"FIX","url":"https://gitlab.com/mailman/postorius/-/issues/531"},{"type":"FIX","url":"https://phabricator.wikimedia.org/T289798"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-08T23:58:03.568247Z"}}