CVE-2026-53612

Publication date 18 June 2026

Last updated 28 October 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.0 · High

Score breakdown

Description

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.

Read the notes from the security team

Status

Package Ubuntu Release Status
util-linux 26.10 stonking
Vulnerable work in progress in 2.42.2-1ubuntu1
26.04 LTS resolute
Fixed in 2.41.3-3ubuntu2.2
25.10 questing Ignored end of life, was needs-triage
24.04 LTS noble
Fixed in 2.39.3-9ubuntu6.6
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Notes

mdeslaur

introduced in 2.39

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
util-linux

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.0 · High

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-8702-1
    • util-linux vulnerabilities
    • 31 August 2026

Other references

Access our resources on patching vulnerabilities