Description
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.
Published: 2026-10-20
Score: 4.7 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

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History

Tue, 20 Oct 2026 16:45:00 +0000

Type Values Removed Values Added
First Time appeared Tox-dev
Tox-dev filelock
Vendors & Products Tox-dev
Tox-dev filelock

Tue, 20 Oct 2026 14:45:00 +0000

Type Values Removed Values Added
Description 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.
Title filelock: SoftFileLock stale-lock break removes a live lock file on a reused inode number and admits two holders
Weaknesses CWE-367
References
Metrics cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N'}


Subscriptions

Tox-dev Filelock
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-10-20T14:32:25.740Z

Reserved: 2026-10-19T21:30:47.244Z

Link: CVE-2026-112935

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-20T15:17:16.243

Modified: 2026-10-20T19:50:26.943

Link: CVE-2026-112935

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-20T17:00:18Z

Weaknesses
  • CWE-367

    Time-of-check Time-of-use (TOCTOU) Race Condition