Time-of-check Time-of-use (TOCTOU) Affecting util-linux package, versions <2.37.2-4ubuntu3.6


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
0.13% (3rd percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-UBUNTU2204-UTILLINUX-17369058
  • published1 Sept 2026
  • disclosed14 Oct 2026

Introduced: 1 Sep 2026

CVE-2026-53613  (opens in a new tab)
CWE-367  (opens in a new tab)

How to fix?

Upgrade Ubuntu:22.04 util-linux to version 2.37.2-4ubuntu3.6 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream util-linux package and not the util-linux package as distributed by Ubuntu. See How to fix? for Ubuntu:22.04 relevant fixed versions and status.

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 Base Scores

version 3.1