Is CVE-2026-53613 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-53613 being exploited in the wild.

How severe is CVE-2026-53613?

High severity, with a CVSS score of 7, published 14 October 2026.

Which products and versions are affected?

Util-Linux 2.17 through 2.41.6, 2.42 through 2.42.3, 2.42.4 (legacy mount path).

How is CVE-2026-53613 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-53613?

Check whether you run Util-Linux at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-53613: util-linux mount TOCTOU privilege escalation via renameat2

CVE-2026-53613 · Severity: high · CVSS 7 · Published 2026-10-14

util-linux is a suite of essential system utilities for Linux. A local low-privileged user with mount privileges can exploit a time-of-check-time-of-use (TOCTOU) flaw in the mount command to redirect authorized mount operations to sensitive system directories, allowing them to mount attacker-controlled content over critical files like /etc/sudoers.d and gain root access.

Technologies: Util-Linux. Vendors: Util-Linux.

Quick answers

Is CVE-2026-53613 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-53613 being exploited in the wild.
How severe is CVE-2026-53613?: High severity, with a CVSS score of 7, published 14 October 2026.
Which products and versions are affected?: Util-Linux 2.17 through 2.41.6, 2.42 through 2.42.3, 2.42.4 (legacy mount path).
Is there a fix for CVE-2026-53613?: Yes: fixed in 2.41.5, 2.42.2, 2.42.4 (with /proc). Until then: Upgrade to fixed versions 2.41.5 or later for the 2.41 series, 2.42.2 or later for the 2.42 series, or use the new mount API instead of the legacy mount(2) path. If /proc is available, ensure systems use the fixed code paths that validate through /proc/self/fd rather than the documented legacy fallback. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-53613 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-53613?: Check whether you run Util-Linux at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 2.41.5, 2.42.2, 2.42.4 (with /proc)

Upgrade to fixed versions 2.41.5 or later for the 2.41 series, 2.42.2 or later for the 2.42 series, or use the new mount API instead of the legacy mount(2) path. If /proc is available, ensure systems use the fixed code paths that validate through /proc/self/fd rather than the documented legacy fallback.

Technical details

The vulnerability exists in util-linux versions 2.17–2.41.6, 2.42–2.42.3, and 2.42.4 (when using legacy mount(2) without /proc), where mount target validation occurs before path re-resolution. A local user can abuse renameat2(RENAME_EXCHANGE) to swap path components between validation and actual mount, redirecting the operation to a root-owned location. The fix pins target file descriptors or uses /proc/self/fd to prevent path manipulation; the documented legacy fallback without /proc remains vulnerable.

Affected products

util-linux util-linux 2.17 through 2.41.6, 2.42 through 2.42.3, 2.42.4 (legacy mount path)

Timeline

2026-10-14: disclosed

References

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