poetry · filelock ReadWriteLock: a crafted lock database makes every acquire stall or hang regardless of timeout
Affects poetrySource GCVE Database
Not known to be exploited · CVSS 5.5 Medium : upgrade to 2.5.1_1 when convenient.
Data as of 30 Oct 2026, 08:30 UTC
- Patch
- Available – fixed in 2.5.1_1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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 poetry to 2.5.1_1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewpoetrypkg:brew/poetryOther 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 and fixed the vulnerability in poetry version 2.5.1_1. Users should upgrade to this version or later. The vulnerability requires the attacker to have write access to the lock database file path, so ensuring that lock directories are sticky and not writable by untrusted users can mitigate the issue. On Linux, enabling the kernel setting fs.protected_regular=2 can prevent opening files owned by other users in world-writable sticky directories. No other specific mitigations are required once patched.
Description
A vulnerability in filelock's ReadWriteLock and AsyncReadWriteLock components allows a local user who can place or overwrite the lock database file to cause every acquire operation to stall or hang indefinitely, ignoring timeout and blocking settings. This results in a denial of service affecting availability only, with no confidentiality or integrity impact. The issue affects filelock versions 3.20.4 through 4.2.0 and requires the attacker to have write access to the lock file path, typically in a non-sticky shared directory or a writable database owned by the lock user. The vulnerability is rated medium severity with a CVSS score of 5.5 and has been fixed in version 2.5.1_1 of the affected product poetry.
References
- github.com/tox-dev/filelock/security/advisories/GHSA-cwqr-hh33-gh44 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-112915 (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)