CVE-2026-53613highCWE-367

CVE-2026-53613: high-severity vulnerability in util-linux

util-linux mount target TOCTOU allows local privilege escalation

Published · Updated

41Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 7epss 0.1%
from disclosure to weapon0 days
Published on NVDOct 14
1st PoCAug 26
exploitation probability
0.1%top 98% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
util-linux is a random collection of Linux utilities. In util-linux 2.17 through 2.41.6 and 2.42 through 2.42.3, and in 2.42.4 when the legacy `mount(2)` path is used without `/proc`, restricted non-root `mount` requests validate an `/etc/fstab` target before the mount operation re-resolves that pathname. A local low-privileged user authorized by an fstab `user` or `users` entry whose target has an attacker-writable ancestor can use `renameat2(RENAME_EXCHANGE)` to swap a path component and redirect an authorized mount to a root-owned location, such as mounting attacker-controlled content over `/etc/sudoers.d`, and thereby gain root privileges. Versions 2.41.5 and 2.42.2 pin targets for the new mount API, and 2.42.4 pins legacy targets through `/proc/self/fd`; the documented legacy fallback without `/proc` remains affected.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
util-linux · util-linux
public PoCs found — 1
githubgithub.com/mohamedjawady/CVE-2026-53613-poc★ 0
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — util-linux

In the same product, most dangerous first.

CVE-2026-76642HIGHutil-linux libmount Privilege Escalation via Failed Mount HelperEPSS 0.2%CVE-2025-14104MEDIUMUtil-linux: util-linux: heap buffer overread in setpwnam() when processing 256-byte usernamesEPSS 0.2%CVE-2026-53615HIGHutil-linux libblkid DOS extended-partition overflow produces invalid partition metadataEPSS 0.2%CVE-2026-53614HIGHutil-linux LIBMOUNT_FORCE_MOUNT2 allows nosuid and noexec bypassEPSS 0.1%CVE-2026-27456MEDIUMutil-linux: TOCTOU Race Condition in util-linux mount(8) - Loop Device SetupEPSS 0.1%CVE-2026-53612HIGHutil-linux mount hook_owner TOCTOU allows local privilege escalationEPSS 0.1%
References
https://github.com/util-linux/util-linux/commit/0b010025a0e429bc80355c94db86a843395d49e2https://github.com/util-linux/util-linux/commit/0d3d55975aa3492c62fd345eac38f41cd166c0b0https://github.com/util-linux/util-linux/commit/2c773f336134acf016e639abb6f12ba7341fe4b8https://github.com/util-linux/util-linux/commit/39fef62bf3226abb6bb018fa8750afa0327e84b4https://github.com/util-linux/util-linux/commit/472cc3fb2d4d47cca7aab2e0b59eb3fb8a9359echttps://github.com/util-linux/util-linux/commit/646fb66603d10a7ac337e14f566f1af48e3107c9https://github.com/util-linux/util-linux/commit/708d1b3c51932dc5ba8082c7368187715e6a8d78https://github.com/util-linux/util-linux/commit/78a860982e036f38fe9c0b3344998df5ac2c2ff5https://github.com/util-linux/util-linux/commit/85d16b341f7232c9dbb4884b632e1e956584bee9https://github.com/util-linux/util-linux/commit/a9508d216eb8977979102782672e0470cc9bf2a2https://github.com/util-linux/util-linux/releases/tag/v2.41.5https://github.com/util-linux/util-linux/releases/tag/v2.42.2