CVE-2026-112912CWE-59

CVE-2026-112912

Low · published October 20, 2026

CVSS v3.1
2.5
EPSS
0%
Percentile
11.0
In the wild
Unconfirmed
What it is

filelock is a platform-independent file lock for Python. From 3.32.6 until 4.2.1, SoftFileLock can follow a swapped symbolic link during the conditional os.access writability check for a node without its owner-write bit, allowing another local user on a platform and directory configuration that follows the link to infer whether a chosen path exists and is writable from the observable acquisition result. This issue is fixed in version 4.2.1.

The record
Technical detail
CVSS v3.1
2.5 · LOW
Vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00213 · 11.0th percentile
Weakness
CWE-59 · Improper Link Resolution Before File Access ('Link Following')
Published
2026-10-20T19:17Z
Affected products (1)
ProductVersionsFixed in
tox-dev/filelock≥ 3.32.6, < 4.2.14.2.1
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-9j6q-wvj5-jgjg · [email protected]https://github.com/tox-dev/filelock/security/advisories/GHSA-9j6q-wvj5-jgjg · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 22 OCT 03:29Z
    EPSS moved — → 0%
    epss
  • 20 OCT 14:23Z
    filelock: Symlink swap during SoftFileLock's writability check leaks whether a path exists and is writable by the lock taker
    cvelistv5
  • 20 OCT 14:23Z
    filelock: Symlink swap during SoftFileLock's writability check leaks whether a path exists and is writable by the lock taker
    cvelistv5