CVE-2026-112935CWE-367

CVE-2026-112935

Medium · published October 20, 2026

CVSS v3.1
4.7
EPSS
0%
Percentile
0.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.7 · MEDIUM
Vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00096 · 0.7th percentile
Weakness
CWE-367 · Time-of-check Time-of-use (TOCTOU) Race Condition
Published
2026-10-20T19:17Z
Affected products (1)
ProductVersionsFixed in
tox-dev/filelock≥ 3.22.0, < 4.2.14.2.1
References (4)
https://github.com/tox-dev/filelock/commit/740ff666b62a88496c8d7394e4e6230605e4d62b · [email protected]https://github.com/tox-dev/filelock/pull/843 · [email protected]https://github.com/tox-dev/filelock/releases/tag/4.2.1 · [email protected]https://github.com/tox-dev/filelock/security/advisories/GHSA-fq56-3cx3-fjxp · [email protected]
EPSS history
Timeline
  • 22 OCT 03:29Z
    EPSS moved — → 0%
    epss
  • 20 OCT 14:32Z
    filelock: SoftFileLock stale-lock break removes a live lock file on a reused inode number and admits two holders
    cvelistv5
  • 20 OCT 14:32Z
    filelock: SoftFileLock stale-lock break removes a live lock file on a reused inode number and admits two holders
    cvelistv5