hatch · filelock: ReadWriteLock on the hard-link route deletes any directory another user renames onto its .filelock-* link
Affects hatchSource GCVE Database
Not known to be exploited · CVSS 6.1 Medium : upgrade to 1.18.1_2 when convenient.
Data as of 27 Oct 2026, 23:27 UTC
- Patch
- Available – fixed in 1.18.1_2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:LExploitation evidence
Disclosed: evidence found.
CVE published 20 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade hatch to 1.18.1_2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewhatchpkg:brew/hatchOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in filelock version 1.18.1_2. Users should upgrade to this version to remediate the vulnerability. The vulnerability is mitigated if the parent directory of the lock database is configured with the sticky bit (e.g., mode 1777) or is not writable by other users, preventing unauthorized renames. No other specific actions are required once patched or if the directory permissions prevent the attack.
Description
A vulnerability in filelock's ReadWriteLock and AsyncReadWriteLock components allows a local user with write permission on the lock database's parent directory to rename directories and cause the lock user's process to recursively delete arbitrary directories. This occurs because the lock cleanup does not verify that the directory it deletes is still the originally created lock directory, enabling deletion of directories renamed onto the expected lock directory name. The issue affects filelock versions 4.1.0 through 4.2.0 on macOS and POSIX systems without a usable /proc/self/fd, such as containers or chroots without /proc. The vulnerability requires a non-sticky, writable shared parent directory and local user privileges. The CVSS 3.1 score is 6.1 (Medium).
References
- github.com/tox-dev/filelock/security/advisories/GHSA-jqc4-5cvw-7w85 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-112937 (opens in a new tab)
- github.com/tox-dev/filelock/pull/834 (opens in a new tab)
- github.com/tox-dev/filelock/commit/5e3f2ec0c5fb17cb2635b60b2b68bc63ab81ca2d (opens in a new tab)
- github.com/tox-dev/filelock (opens in a new tab)
- github.com/tox-dev/filelock/releases/tag/4.2.1 (opens in a new tab)