CVE-2026-112935
mediumfilelock is a platform-independent file lock for Python.
Vendor / product: Tox-dev — filelock
filelock is a platform-independent file lock for Python. From 3.22.0 until 4.2.1, SoftFileLock can break a stale marker after an attacker frees its own marker following the stale read, an honest contender creates a live successor on the reused inode, and the successor's modification time is not newer than the saved observation, causing the live marker to be removed and two holders to be admitted. This issue is fixed in version 4.2.1.
CVSS
4.7
4.7 (CVSS v3.1)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N Severity source: NVD CVSS v3.1 (security-advisories@github.com)
Timeline (UTC)
Published: 2026-10-20 15:17
Modified: 2026-10-28 15:17
NVD status: Modified
Last synced 14 hours ago
Verified against the source API 2026-10-28 15:27 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
tox-dev / filelock ≥3.22.0 <4.2.1
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
Patch / mitigation: https://github.com/tox-dev/filelock/commit/740ff666b62a88496c8d7394e4e6230605e4d62b
Patch / mitigation: https://github.com/tox-dev/filelock/pull/843
Patch / mitigation: https://github.com/tox-dev/filelock/security/advisories/GHSA-fq56-3cx3-fjxp
Patch / mitigation: https://github.com/tox-dev/filelock/security/advisories/GHSA-fq56-3cx3-fjxp
References
- https://github.com/tox-dev/filelock/commit/740ff666b62a88496c8d7394e4e6230605e4d62b security-advisories@github.com
- https://github.com/tox-dev/filelock/pull/843 security-advisories@github.com
- https://github.com/tox-dev/filelock/releases/tag/4.2.1 security-advisories@github.com
- https://github.com/tox-dev/filelock/security/advisories/GHSA-fq56-3cx3-fjxp security-advisories@github.com
- https://github.com/tox-dev/filelock/security/advisories/GHSA-fq56-3cx3-fjxp 134c704f-9b21-4f2e-91b3-4a467353bcc0
Data sources
NVD CVE API 2.0 — fetched 2026-10-28 15:27 UTC · record ↗