shodan · filelock: ReadWriteLock on the hard-link route deletes any directory another user renames onto its .filelock-* link
Affects shodanSource GCVE Database
Not known to be exploited · CVSS 6.1 Medium : upgrade to 1.31.0_12 when convenient.
Data as of 30 Oct 2026, 05:16 UTC
- Patch
- Available – fixed in 1.31.0_12
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
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 shodan to 1.31.0_12.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewshodanpkg:brew/shodanOther 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 1.31.0_12 (4.2.1). Users should upgrade to this version or later to remediate the vulnerability. The vulnerability is mitigated if the parent directory of the lock database has the sticky bit set (e.g., mode 1777), preventing unauthorized renames by other users. Ensuring that directories containing lock files are not writable by untrusted users or have appropriate sticky bit permissions can also reduce risk.
Description
The filelock library versions 4.1.0 through 4.2.0 contain a vulnerability in the ReadWriteLock and AsyncReadWriteLock mechanisms where private .filelock-* directories are deleted recursively without verifying the directory's identity. This can be exploited by another local user who can rename directories in the shared parent directory (without sticky bit protection) to cause the lock user's process to delete arbitrary directories with the lock user's permissions. The issue affects macOS since version 4.1.1 and POSIX systems without a usable /proc/self/fd, such as chroot or containers without /proc mounted. The vulnerability has a CVSS 3.1 score of 6.1 (Medium) and results in high integrity impact due to unauthorized deletion of directory trees.
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)