util-linux LIBMOUNT_FORCE_MOUNT2 allows nosuid and noexec bypass
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 2.41.5, 2.42.2
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
util-linux is a random collection of Linux utilities. In util-linux 2.39.1 through 2.41.4 and 2.42 through 2.42.1, the SUID `mount` utility reads the attacker-controlled `LIBMOUNT_FORCE_MOUNT2` environment variable with `getenv()`, allowing a local low-privileged user to force the non-atomic legacy bind-mount path. With an `/etc/fstab` bind mount authorized by `user` or `users` and protected by `nosuid`, `noexec`, or `nodev`, an attacker can race the window between the initial bind mount and the remount that applies those security flags and execute a SUID program from the temporarily unprotected mount, potentially gaining root privileges. This issue is fixed in 2.41.5 and 2.42.2.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- util-linux util-linux
From 2.39.1 · fixed in 2.41.5; From 2.42 · fixed in 2.42.2