{"cve":"CVE-2021-40347","nvd":{"published":"2021-09-10T19:15:08.163","modified":"2026-06-17T04:06:46.343","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","score":5.4},"cwes":[],"references":["https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=993746","https://gitlab.com/mailman/postorius/-/commit/3d880c56b58bc26b32eac0799407d74b64b7474b","https://gitlab.com/mailman/postorius/-/issues/531","https://gitlab.com/mailman/postorius/-/tags","https://phabricator.wikimedia.org/T289798"],"products":["postorius_project:postorius"],"source":"nvd","synced_at":"2026-10-19T21:23:41.316049955+00:00"},"epss":{"cve":"CVE-2021-40347","score":0.01186,"percentile":0.67859,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-v83x-78q3-gr2j","url":"https://osv.dev/vulnerability/GHSA-v83x-78q3-gr2j","summary":"GNU Mailman Postorius Access Control Issues","modified":"2024-10-21T20:26:03.468341Z","packages":[{"ecosystem":"PyPI","name":"postorius","purl":"pkg:pypi/postorius","ranges":["<1.3.5"],"fixed":["1.3.5"]}]},{"id":"PYSEC-2021-319","url":"https://osv.dev/vulnerability/PYSEC-2021-319","summary":"","modified":"2026-06-10T17:01:35.187803742Z","packages":[{"ecosystem":"PyPI","name":"postorius","purl":"pkg:pypi/postorius","ranges":["<1.3.5"],"fixed":["1.3.5"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}