High 7.0Published Oct 14, 2026

CVE-2026-53612util-linux mount hook_owner TOCTOU allows local privilege escalation

Updated under an hour ago (Oct 27, 2026, 7:23 AM ET)

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EPSS puts the chance of exploitation in the next 30 days at 0.15%, higher than 4% of scored CVEs.

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Every CVE for util-linux

Exploited in the last 30 days

util-linux is a random collection of Linux utilities. In util-linux 2.39 through 2.41.4 and 2.42 through 2.42.1, the SUID `mount` utility's `hook_owner.c` post-mount hook performs path-based `chmod()` and `lchown()` operations on a previously validated mount target. A local low-privileged user authorized by an `/etc/fstab` entry with `user` or `users` and an `X-mount.mode`, `X-mount.owner`, or `X-mount.group` option can use `renameat2(RENAME_EXCHANGE)` to race a writable ancestor of the target and redirect the privileged ownership or mode change to a root-owned path, potentially gaining root privileges. This issue is fixed in 2.41.5 and 2.42.2.

CVSS: 7.0 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-367
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.15% (percentile 4)
Assigned by: GitHub_M
NVD analysis: Awaiting Analysis
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

util-linux util-linux util_linux:util_linux (from the name)	from 2.39, < 2.41.5; from 2.42, < 2.42.2	CNA record

References

References

https://github.com/util-linux/util-linux/security/advisories/GHSA-g8wm-75wr-g2vh	x-refsource-confirm
https://github.com/util-linux/util-linux/commit/24da33905c7115c4cbccd0afb2a469804e96467a	x-refsource-misc
https://github.com/util-linux/util-linux/commit/722c96974dd4009a334e4aee556eedaab5fb94b4	x-refsource-misc
https://github.com/util-linux/util-linux/commit/897a08c2b11dfa66975c3d24d63c7bf5f5be1a7c	x-refsource-misc
https://github.com/util-linux/util-linux/commit/d0c5adaeb3a3d823aba1377794de8f009b8152cc	x-refsource-misc
https://github.com/util-linux/util-linux/releases/tag/v2.41.5	x-refsource-misc
https://github.com/util-linux/util-linux/releases/tag/v2.42.2	x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.