Affected: Alpaquita:25: util-linux, Alpaquita:stream: util-linux, BellSoft Hardened Containers:25: util-linux, BellSoft Hardened Containers:stream: util-linux

Affected: CleanStart: util-linux

Security vulnerability affects the util-linux package. util-linux is a random collection of Linux utilities.

util-linux is a random collection of Linux utilities. Prior to version 2.41.4, a TOCTOU (Time-of-Check-Time-of-Use) vulnerability has been identified in the SUID binary /usr/bin/mount from util-linux. The mount binary, when setting up loop devices, validates the source file path with user privileges via fork() + setuid() + realpath(), but subsequently re-canonicalizes and opens it with root privileges (euid=0) without verifying that the path has not been replaced between both operations. Neither O_NOFOLLOW, nor inode comparison, nor post-open fstat() are employed. This allows a local unprivileged user to replace the source file with a symlink pointing to any root-owned file or device during the race window, causing the SUID binary to open and mount it as root. Exploitation requires an /etc/fstab entry with user,loop options whose path points to a directory where the attacker has write permission, and that /usr/bin/mount has the SUID bit set (the default configuration on virtually all Linux distributions). The impact is unauthorized read access to root-protected files and block devices, including backup images, disk volumes, and any file containing a valid filesystem. This issue has been patched in version 2.41.4.

Affected: openEuler:20.03-LTS-SP4: util-linux, openEuler:22.03-LTS-SP4: util-linux, openEuler:24.03-LTS: util-linux, openEuler:24.03-LTS-SP1: util-linux, openEuler:24.03-LTS-SP3: util-linux

The util-linux package contains a random collection of files that implements some low-level basic linux utilities. Security Fix(es):

util-linux is a random collection of Linux utilities. Prior to version 2.41.4, a TOCTOU (Time-of-Check-Time-of-Use) vulnerability has been identified in the SUID binary /usr/bin/mount from util-linux. The mount binary, when setting up loop devices, validates the source file path with user privileges via fork() + setuid() + realpath(), but subsequently re-canonicalizes and opens it with root privileges (euid=0) without verifying that the path has not been replaced between both operations. Neither O_NOFOLLOW, nor inode comparison, nor post-open fstat() are employed. This allows a local unprivileged user to replace the source file with a symlink pointing to any root-owned file or device during the race window, causing the SUID binary to open and mount it as root. Exploitation requires an /etc/fstab entry with user,loop options whose path points to a directory where the attacker has write permission, and that /usr/bin/mount has the SUID bit set (the default configuration on virtually all Linux distributions). The impact is unauthorized read access to root-protected files and block devices, including backup images, disk volumes, and any file containing a valid filesystem. This issue has been patched in version 2.41.4.(CVE-2026-27456)

libblkid-devel-2.42-1.1 on GA media

util-linux: util-linux: Heap buffer overread in setpwnam() when processing 256-byte usernames util-linux: util-linux: Access control bypass due to improper hostname canonicalization util-linux: TOCTOU in the mount program when setting up loop devices

Security update for util-linux

Affected: Ubuntu:14.04:LTS: util-linux, Ubuntu:Pro:16.04:LTS: util-linux, Ubuntu:18.04:LTS: util-linux, Ubuntu:Pro:20.04:LTS: util-linux, Ubuntu:22.04:LTS: util-linux, Ubuntu:24.04:LTS: util-linux, Ubuntu:25.10: util-linux, Ubuntu:26.04:LTS: util-linux

util-linux is a random collection of Linux utilities. Prior to version 2.41.4, a TOCTOU (Time-of-Check-Time-of-Use) vulnerability has been identified in the SUID binary /usr/bin/mount from util-linux. The mount binary, when setting up loop devices, validates the source file path with user privileges via fork() + setuid() + realpath(), but subsequently re-canonicalizes and opens it with root privileges (euid=0) without verifying that the path has not been replaced between both operations. Neither O_NOFOLLOW, nor inode comparison, nor post-open fstat() are employed. This allows a local unprivileged user to replace the source file with a symlink pointing to any root-owned file or device during the race window, causing the SUID binary to open and mount it as root. Exploitation requires an /etc/fstab entry with user,loop options whose path points to a directory where the attacker has write permission, and that /usr/bin/mount has the SUID bit set (the default configuration on virtually all Linux distributions). The impact is unauthorized read access to root-protected files and block devices, including backup images, disk volumes, and any file containing a valid filesystem. This issue has been patched in version 2.41.4.