gam · filelock: StrictSoftFileLock creates its claim directories without the lock mode, so another local user with a write
Affects gamSource GCVE Database
Not known to be exploited · CVSS 5.3 Medium.
Data as of 9 Nov 2026, 20:05 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 5.3 |
|---|
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:LExploitation evidence
Disclosed: evidence found.
CVE published 5 Nov 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 9 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewgampkg:brew/gamOther 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
Users should ensure that the umask and default ACL settings do not leave the claim directories writable by other local users. Specifically, avoid umask 000 in sticky directories like /tmp and do not grant group write permissions via default ACLs on the lock's parent directory. Existing <path>.filelock directories created by affected versions should be manually removed or have their permissions corrected to prevent unauthorized write access. Monitor vendor advisories for any official fixes.
Description
The vulnerability in filelock versions 3.30.0 through 4.2.0 involves the creation of claim directories without restrictive permissions, allowing other local users with write access to those directories to unlink claim files. This can lead to multiple holders simultaneously writing protected data without detection, causing integrity issues. The flaw requires specific conditions related to umask and default ACL settings that leave the claim directories writable by other users. The impact is limited to local users and does not affect confidentiality but can compromise data integrity and availability.
References
- github.com/tox-dev/filelock/security/advisories/GHSA-6627-m3xw-93mp (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)