Race Condition Enabling Link Following Affecting filelock package, versions [3.20.4,4.2.1)
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-21280753
- published20 Oct 2026
- disclosed20 Oct 2026
- creditAnthropic's OSS Scanner
Introduced: 20 Oct 2026
NewCVE-2026-112940 (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 Race Condition Enabling Link Following via the read-write lock implementation in src/filelock/_read_write.py, where the SQLite lock database is opened using a shared, predictable name in a directory where another user can manipulate names. An attacker who controls names in the lock database's directory can redirect the lock file path to an arbitrary location, allowing them to corrupt or overwrite files with the victim's privileges.
Note: This is only exploitable when another user has write access to the directory containing the lock database.