lexicon · filelock: StrictSoftFileLock and SoftReadWriteLock adopt a protocol directory another user created first, losing
Affects lexiconSource GCVE Database
Not known to be exploited · CVSS 6.3 Medium : upgrade to 3.25.2_5 when convenient.
Data as of 30 Oct 2026, 07:32 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 6.3 |
|---|
- Patch
- Available – fixed in 3.25.2_5
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/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 lexicon to 3.25.2_5.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewlexiconpkg:brew/lexiconOther 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 3.25.2_5 that addresses this issue. Users should upgrade to this fixed version or later. Until patched, avoid using new lock paths in shared sticky directories like /tmp where other local users can pre-create the protocol directory. There are no vendor advisories indicating that no action is required or that the issue is already mitigated.
Description
The vulnerability involves the StrictSoftFileLock and SoftReadWriteLock classes adopting a protocol directory created by another local user before the lock user's first acquire operation. This allows the other user to interfere with the lock state by unlinking claims or redirecting lock operations, potentially causing multiple writers to enter a critical section simultaneously and causing denial of service by spinning or memory exhaustion. The issue affects filelock versions 3.30.0 through 4.2.0 and requires the attacker to create the directory first in a shared sticky directory like /tmp. The CVSS 3.1 score is 6.3 (Medium).
References
- github.com/tox-dev/filelock/security/advisories/GHSA-9c4x-gm8v-wgc4 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-112911 (opens in a new tab)
- github.com/tox-dev/filelock/pull/839 (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)