Symlink Attack Affecting filelock package, versions [3.32.6,4.2.1)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-FILELOCK-21280761
- published20 Oct 2026
- disclosed20 Oct 2026
- creditUnknown
Introduced: 20 Oct 2026
NewCVE-2026-112912 (opens in a new tab)How to fix?
Upgrade filelock to version 4.2.1 or higher.
Overview
Affected versions of this package are vulnerable to Symlink Attack via the lock file open logic in _api.py and related platform backends, where an existing lock file's permissions are not preserved on Unix systems. An attacker with local access can observe the file mode applied to a newly created lock file, potentially reading its contents or inferring sensitive path information that would otherwise be restricted by the original file's ACL.