{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "3.30.0"
                  },
                  {
                    "fixed": "4.2.1"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              },
              {
                "range": [
                  {
                    "fixed": "bfa066d65a1ba9106f86ee9d027f7588b9c77e03"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "original_tag": "4.2.1",
                "range": [
                  {
                    "fixed": "60331bb89f325020b48bc51bde904c6446384e4a"
                  }
                ],
                "source": "REFERENCES_TAG"
              }
            ]
          },
          "events": [
            {
              "introduced": "1b094069044a3f2a39173ae841eb22b274833ff9"
            },
            {
              "fixed": "60331bb89f325020b48bc51bde904c6446384e4a"
            },
            {
              "fixed": "bfa066d65a1ba9106f86ee9d027f7588b9c77e03"
            }
          ],
          "repo": "https://github.com/tox-dev/filelock",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-9c4x-gm8v-wgc4"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-283"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/112xxx/CVE-2026-112911.json"
  },
  "details": "filelock is a platform-independent file lock for Python. From 3.30.0 until 4.2.1, StrictSoftFileLock versions from 3.30.0 and SoftReadWriteLock versions from 4.0.0 can adopt a protocol directory created first by another local user in a shared parent directory, allowing that user to alter protocol state and admit concurrent holders. This issue is fixed in version 4.2.1.",
  "id": "CVE-2026-112911",
  "modified": "2026-10-22T02:30:47.449819023Z",
  "published": "2026-10-20T14:21:24.480Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/112xxx/CVE-2026-112911.json"
    },
    {
      "type": "FIX",
      "url": "https://github.com/tox-dev/filelock/commit/bfa066d65a1ba9106f86ee9d027f7588b9c77e03"
    },
    {
      "type": "FIX",
      "url": "https://github.com/tox-dev/filelock/pull/839"
    },
    {
      "type": "WEB",
      "url": "https://github.com/tox-dev/filelock/releases/tag/4.2.1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/tox-dev/filelock/security/advisories/GHSA-9c4x-gm8v-wgc4"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-112911"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "filelock: StrictSoftFileLock and SoftReadWriteLock adopt a protocol directory another user created first, losing mutual exclusion"
}