# CVE-2026-13595: Util-linux: util-linux: heap use-after-free in libblkid nested partition probing

Status: published. Published: 2026-06-29. Updated: 2026-11-02.

A flaw was found in the libblkid library of util-linux. During nested partition probing, the BSD, Minix, Solaris x86, and UnixWare partition probers cache a raw pointer to a parent partition entry in a dynamically allocated array. When subsequent partition additions cause the array to be reallocated, this pointer becomes stale, leading to a heap use-after-free read. An attacker who can present a crafted block device image (for example, via USB insertion or a loop-mounted disk image) can trigger this flaw without user interaction, as libblkid is invoked automatically by udev/udisks as root on block-device hot-plug events. This could lead to limited information disclosure or denial of service.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (util-linux): ≥ 0:2.40.2-18.el10_2.20; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Hardened Images (util-linux-main): ≥ 2.42.2-1.hum1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (util-linux): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (util-linux): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (util-linux): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-8): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-9): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 5 (openshift/ose-rhel-coreos-9): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.8 (medium); CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.14% as of 2026-11-01; percentile 3.71%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-416

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2026:26573 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:93461 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-13595 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2494101 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://github.com/util-linux/util-linux/commit/c0186f14fbdb02f64c8e0ba701ce727ea764ff4c (CNA: redhat)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-13595; retrieved 2026-11-02; source updated 2026-11-02

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-13595; retrieved 2026-11-02; source updated Not reported

Revision: 45d1de65e2f0270a7f85d82c7d3c0bdba4f5361b6d74609d451a8540955784cc

Canonical: https://y2.dev/cve/CVE-2026-13595