Security update for python-filelock SUSE Patch security@suse.de SUSE Security Team SUSE-SU-2026:20216-1 Final 1 1 2026-01-30T21:26:21Z current 2026-01-30T21:26:21Z 2026-01-30T21:26:21Z cve-database/bin/generate-cvrf.pl 2017-02-24T01:00:00Z Security update for python-filelock This update for python-filelock fixes the following issues: - CVE-2025-68146: TOCTOU race condition may allow local attackers to corrupt or truncate arbitrary user files (bsc#1255244). - CVE-2026-22701: TOCTOU race condition in the SoftFileLock implementation (bsc#1256457). The CVRF data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0). SUSE-SLES-16.0-229 Copyright SUSE LLC under the Creative Commons License 4.0 with Attribution (CC-BY-4.0) https://www.suse.com/support/update/announcement/2026/suse-su-202620216-1/ Link for SUSE-SU-2026:20216-1 https://lists.suse.com/pipermail/sle-security-updates/2026-February/024068.html E-Mail link for SUSE-SU-2026:20216-1 https://www.suse.com/support/security/rating/ SUSE Security Ratings https://bugzilla.suse.com/1255244 SUSE Bug 1255244 https://bugzilla.suse.com/1256457 SUSE Bug 1256457 https://www.suse.com/security/cve/CVE-2025-68146/ SUSE CVE CVE-2025-68146 page https://www.suse.com/security/cve/CVE-2026-22701/ SUSE CVE CVE-2026-22701 page SUSE Linux Enterprise Server 16.0 SUSE Linux Enterprise Server for SAP applications 16.0 python313-filelock-3.18.0-160000.3.1 python313-filelock-3.18.0-160000.3.1 as a component of SUSE Linux Enterprise Server 16.0 python313-filelock-3.18.0-160000.3.1 as a component of SUSE Linux Enterprise Server for SAP applications 16.0 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. CVE-2025-68146 SUSE Linux Enterprise Server 16.0:python313-filelock-3.18.0-160000.3.1 SUSE Linux Enterprise Server for SAP applications 16.0:python313-filelock-3.18.0-160000.3.1 moderate To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2026/suse-su-202620216-1/ https://www.suse.com/security/cve/CVE-2025-68146.html CVE-2025-68146 https://bugzilla.suse.com/1255244 SUSE Bug 1255244 filelock is a platform-independent file lock for Python. Prior to version 3.20.3, a TOCTOU race condition vulnerability exists in the SoftFileLock implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly. The vulnerability occurs in the _acquire() method between raise_on_not_writable_file() (permission check) and os.open() (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service. This issue has been patched in version 3.20.3. CVE-2026-22701 SUSE Linux Enterprise Server 16.0:python313-filelock-3.18.0-160000.3.1 SUSE Linux Enterprise Server for SAP applications 16.0:python313-filelock-3.18.0-160000.3.1 moderate To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2026/suse-su-202620216-1/ https://www.suse.com/security/cve/CVE-2026-22701.html CVE-2026-22701 https://bugzilla.suse.com/1256457 SUSE Bug 1256457