Kernel: >> Util-Linux >> 2.31 Security Vulnerabilities
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.
CVSS Score
4.7
EPSS Score
0.0
Published
2026-04-03
wall in util-linux through 2.40, often installed with setgid tty permissions, allows escape sequences to be sent to other users' terminals through argv. (Specifically, escape sequences received from stdin are blocked, but escape sequences received from argv are not blocked.) There may be plausible scenarios where this leads to account takeover.
CVSS Score
3.3
EPSS Score
0.102
Published
2024-03-27
A flaw was found in the util-linux chfn and chsh utilities when compiled with Readline support. The Readline library uses an "INPUTRC" environment variable to get a path to the library config file. When the library cannot parse the specified file, it prints an error message containing data from the file. This flaw allows an unprivileged user to read root-owned files, potentially leading to privilege escalation. This flaw affects util-linux versions prior to 2.37.4.
CVSS Score
5.5
EPSS Score
0.0
Published
2022-02-21
An integer overflow in util-linux through 2.37.1 can potentially cause a buffer overflow if an attacker were able to use system resources in a way that leads to a large number in the /proc/sysvipc/sem file. NOTE: this is unexploitable in GNU C Library environments, and possibly in all realistic environments.
CVSS Score
5.5
EPSS Score
0.001
Published
2021-07-30
In util-linux before 2.32-rc1, bash-completion/umount allows local users to gain privileges by embedding shell commands in a mountpoint name, which is mishandled during a umount command (within Bash) by a different user, as demonstrated by logging in as root and entering umount followed by a tab character for autocompletion.
CVSS Score
7.8
EPSS Score
0.001
Published
2018-03-07