CVE-2025-68146 (Medium) detected in filelock-3.19.1-py3-none-any.whl

[mend-bolt-for-github]

CVE-2025-68146 - Medium Severity Vulnerability

Vulnerable Library - filelock-3.19.1-py3-none-any.whl

A platform independent file lock.

Library home page: https://files.pythonhosted.org/packages/42/14/42b2651a2f46b022ccd948bca9f2d5af0fd8929c4eec235b8d6d844fbe67/filelock-3.19.1-py3-none-any.whl

Path to dependency file: /requirements.txt

Path to vulnerable library: /tmp/ws-ua_20260123034312_WUBMDO/python_ENHXDJ/202601230345391/env/lib/python3.9/site-packages/filelock-3.19.1.dist-info

Dependency Hierarchy:

• scrapy-2.13.4-py3-none-any.whl (Root Library)
  • tldextract-5.3.0-py3-none-any.whl
    • ❌ filelock-3.19.1-py3-none-any.whl (Vulnerable Library)

Found in HEAD commit: ef3d24fa88d80ad14eb3a3575dccaaa2f74d313d

Found in base branch: main

Vulnerability Details

filelock is a platform-independent file lock for Python. In versions prior to 3.20.1, a Time-of-Check-Time-of-Use (TOCTOU) race condition allows local attackers to corrupt or truncate arbitrary user files through symlink attacks. The vulnerability exists in both Unix and Windows lock file creation where filelock checks if a file exists before opening it with O_TRUNC. An attacker can create a symlink pointing to a victim file in the time gap between the check and open, causing os.open() to follow the symlink and truncate the target file. All users of filelock on Unix, Linux, macOS, and Windows systems are impacted. The vulnerability cascades to dependent libraries. The attack requires local filesystem access and ability to create symlinks (standard user permissions on Unix; Developer Mode on Windows 10+). Exploitation succeeds within 1-3 attempts when lock file paths are predictable. The issue is fixed in version 3.20.1. If immediate upgrade is not possible, use SoftFileLock instead of UnixFileLock/WindowsFileLock (note: different locking semantics, may not be suitable for all use cases); ensure lock file directories have restrictive permissions (chmod 0700) to prevent untrusted users from creating symlinks; and/or monitor lock file directories for suspicious symlinks before running trusted applications. These workarounds provide only partial mitigation. The race condition remains exploitable. Upgrading to version 3.20.1 is strongly recommended.

Publish Date: 2025-12-16

URL: CVE-2025-68146

CVSS 3 Score Details (6.3)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Local
  • Attack Complexity: High
  • Privileges Required: Low
  • User Interaction: None
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: None
  • Integrity Impact: High
  • Availability Impact: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Release Date: 2025-12-16

Fix Resolution: filelock - 3.20.1

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[mend-bolt-for-github]

✔️ This issue was automatically closed by Mend because the vulnerable library in the specific branch(es) was either marked as ignored or it is no longer part of the Mend inventory.

[mend-bolt-for-github]

ℹ️ This issue was automatically re-opened by Mend because the vulnerable library in the specific branch(es) has been detected in the Mend inventory.