Security advisory

{
  "id": "8c9e361e66425b19112c2a4050b82c4e93268b9b828e5e2625d8ab3872e48d43",
  "url": "https://osv.dev/vulnerability/CVE-2021-40347",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-40347",
    "summary": "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.",
    "evidence": "osv:CVE-2021-40347",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2021-40347",
      "aliases": [
        "CVE-2021-40347",
        "GHSA-v83x-78q3-gr2j",
        "PYSEC-2021-319"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://gitlab.com/mailman/postorius",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "e2d06746acad481e889de200dc1de503cab35874"
                },
                {
                  "fixed": "3d880c56b58bc26b32eac0799407d74b64b7474b"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:postorius_project:postorius:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.3.5"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "3d880c56b58bc26b32eac0799407d74b64b7474b"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.3.4",
            "1.3.4rc1",
            "1.3.3",
            "1.3.3rc2",
            "1.3.3rc1",
            "1.3.2",
            "1.3.1",
            "1.3.0",
            "1.2.4",
            "1.2.3",
            "1.2.2",
            "1.2.1",
            "1.2.0",
            "1.1.2",
            "1.1.0",
            "1.0.2",
            "1.0.1",
            "1.0.0",
            "1.0.0b2",
            "1.0.0b1",
            "postorius-1.0.0a-pypi",
            "postorius-1.0.0a1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-40347.json"
          }
        }
      ],
      "modified": "2026-10-20T10:54:58.007090669Z",
      "provider": "osv",
      "references": [
        "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=993746",
        "https://gitlab.com/mailman/postorius/-/tags",
        "https://www.debian.org/security/2021/dsa-4970",
        "https://gitlab.com/mailman/postorius/-/commit/3d880c56b58bc26b32eac0799407d74b64b7474b",
        "https://gitlab.com/mailman/postorius/-/issues/531",
        "https://phabricator.wikimedia.org/T289798"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-40347",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 386572,
  "published_at": "2021-09-10T19:15:08.163+00:00"
}