scrapy · filelock: Symlink swap during SoftFileLock's writability check leaks whether a path exists and is writable by the lock
Affects scrapySource GCVE Database
Not known to be exploited · CVSS 2.5 Low : upgrade to 2.19.0_2 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.19.0_2
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:NExploitation 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 scrapy to 2.19.0_2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewscrapypkg:brew/scrapyOther 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 2.19.0_2. Users should upgrade to this version or later to remediate the vulnerability. On Linux, enabling the fs.protected_symlinks kernel setting (default in many distributions) mitigates the issue in sticky world-writable directories such as /tmp. Avoid using lock directories that are world-writable without the sticky bit or sticky group-writable directories without kernel protections. No other specific mitigations are required.
Description
A symlink swap vulnerability in filelock's SoftFileLock writability check allows a local user to leak one bit of information about whether a path exists and is writable by the lock user. This occurs because the check uses os.lstat followed by os.access, which follows symlinks, enabling a time-of-check to time-of-use (TOCTOU) leak. The vulnerability affects filelock versions 3.32.6 through 4.2.0 and is mitigated on Linux by the fs.protected_symlinks kernel setting in common sticky world-writable directories like /tmp. The impact is limited to leaking a single bit per acquire attempt, with no integrity or availability impact. The vulnerability requires local access, the ability to create entries in the lock directory, and high timing precision to exploit.
References
- github.com/tox-dev/filelock/security/advisories/GHSA-9j6q-wvj5-jgjg (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-112912 (opens in a new tab)
- github.com/tox-dev/filelock/pull/835 (opens in a new tab)
- github.com/tox-dev/filelock/commit/e1e825b1992f69fb6b346dc395d5ae4893536c0a (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)