hatch · filelock: SoftReadWriteLock holder refresh writes through a hard link and hangs on a named pipe that another local
Affects hatchSource GCVE Database
Not known to be exploited · CVSS 6.1 Medium : upgrade to 1.18.1_2 when convenient.
Data as of 30 Oct 2026, 09:01 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 6.1 |
|---|
- Patch
- Available – fixed in 1.18.1_2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:HExploitation evidence
Disclosed: evidence found.
CVE published 20 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 29 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 patch is available in filelock version 1.18.1_2 that fixes this vulnerability. Users should upgrade to this version or later to remediate the issue. No other mitigation is indicated or required by the vendor advisory.
Description
A vulnerability in filelock versions >=1.18.1_1 and <1.18.1_2 allows a local user who owns the lock's .rw directory tree to interfere with the SoftReadWriteLock holder refresh mechanism. This can cause the lock user's write_lock() or read_lock() calls to hang indefinitely when a named pipe (FIFO) is involved, preventing the heartbeat thread from running and leading to multiple processes believing they hold the write lock simultaneously. Additionally, on Linux systems with permissive hard-link policies, the attacker can cause the lock user to overwrite part of one of its own private files via a hard link. The vulnerability has a CVSS score of 6.1 (Medium) and requires local access with low privileges. A fix is available in version 1.18.1_2.
References
- github.com/tox-dev/filelock/security/advisories/GHSA-fj95-fr6c-h845 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-112934 (opens in a new tab)
- github.com/tox-dev/filelock/pull/842 (opens in a new tab)
- github.com/tox-dev/filelock/commit/bfa066d65a1ba9106f86ee9d027f7588b9c77e03 (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)