CVE-2026-112912 (GCVE-0-2026-112912)
Vulnerability from cvelistv5 – Published: 2026-10-20 14:23 – Updated: 2026-10-20 15:37
VLAI
EPSS
VEX
Title
filelock: Symlink swap during SoftFileLock's writability check leaks whether a path exists and is writable by the lock taker
Summary
filelock is a platform-independent file lock for Python. From 3.32.6 until 4.2.1, SoftFileLock can follow a swapped symbolic link during the conditional os.access writability check for a node without its owner-write bit, allowing another local user on a platform and directory configuration that follows the link to infer whether a chosen path exists and is writable from the observable acquisition result. This issue is fixed in version 4.2.1.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-20 15:37 UTC
CWE
- CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/tox-dev/filelock/security/advi… | x_refsource_CONFIRM |
| https://github.com/tox-dev/filelock/pull/835 | x_refsource_MISC |
| https://github.com/tox-dev/filelock/commit/e1e825… | x_refsource_MISC |
| https://github.com/tox-dev/filelock/releases/tag/4.2.1 | x_refsource_MISC |
Impacted products
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| Author | Source | Type | Date | Other |
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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