CVE-2026-112909CWE-706

CVE-2026-112909

Medium · published October 20, 2026

CVSS v3.1
6.1
EPSS
0%
Percentile
1.6
In the wild
Unconfirmed
What it is

filelock is a platform-independent file lock for Python. Prior to 4.2.1, UnixFileLock can truncate a regular file renamed onto the lock path when another local user has actual rename permission, or hard-linked there under a permissive hard-link policy; when an explicit mode is requested, affected versions from 3.10.2 can also change that file's mode. This issue is fixed in version 4.2.1.

The record
Technical detail
CVSS v3.1
6.1 · MEDIUM
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00118 · 1.6th percentile
Weakness
CWE-706 · Use of Incorrectly-Resolved Name or Reference
Published
2026-10-20T19:17Z
References (5)
https://github.com/tox-dev/filelock/commit/e1e825b1992f69fb6b346dc395d5ae4893536c0a · [email protected]https://github.com/tox-dev/filelock/pull/835 · [email protected]https://github.com/tox-dev/filelock/releases/tag/4.2.1 · [email protected]https://github.com/tox-dev/filelock/security/advisories/GHSA-69hj-f68j-2879 · [email protected]https://github.com/tox-dev/filelock/security/advisories/GHSA-69hj-f68j-2879 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 22 OCT 03:29Z
    EPSS moved — → 0%
    epss
  • 20 OCT 14:16Z
    filelock: UnixFileLock truncates and chmods any regular file another user renames or hard-links onto the lock path
    cvelistv5
  • 20 OCT 14:16Z
    filelock: UnixFileLock truncates and chmods any regular file another user renames or hard-links onto the lock path
    cvelistv5