CVE-2026-112934

filelock: SoftReadWriteLock holder refresh writes through a hard link and hangs on a named pipe that another local user renames over its record

MEDIUM
6.1
CVSS Score
Published: October 20, 2026 at 02:30 PM UTC
Updated: October 22, 2026 at 10:18 PM UTC
1 product affected across 1 vendorFilelock

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Severity
MEDIUM6.1
Exploit prediction
EPSS 0.2%
SSVC
PoC

Description

filelock is a platform-independent file lock for Python. From 4.0.0 until 4.2.1, SoftReadWriteLock refreshes holder records by name, allowing another local user with rename access to the lock directory to replace a record with a named pipe and stall the lock, or under a permissive hard-link policy to link a reachable target file and cause the lock user to write through it. This issue is fixed in version 4.2.1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

4.0.0 ≤ v < 4.2.1

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/tox-dev/filelock/security/advisories/GHSA-fj95-fr6c-h845
x_refsource_MISCPatch
Source: cverecord
https://github.com/tox-dev/filelock/pull/842
x_refsource_MISCRelease Notes
Source: cverecord
https://github.com/tox-dev/filelock/releases/tag/4.2.1

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.1MEDIUMGitHub_M
Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-62

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