---
id: CVE-2026-89574
title: 'kernel: dm array: validate array block headers on read (CVE-2026-89574)'
summary: >-
  A flaw was found in the Linux kernel's device mapper (dm) array component.
  Insufficient validation of array block headers during read operations allows a
  local attacker to craft a malicious on-disk `nr_entries` value. This can lead
  to an o…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-125
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 6
  - enterprise_linux 7
  - enterprise_linux 8
  - enterprise_linux 9
  - openshift_container_platform 4
published: '2026-09-11'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T22:07:33+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89574.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89574.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89574'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532117'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89574'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89574'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89574.mbox
  - url: 'https://git.kernel.org/stable/c/2965787723084835b18dfe993cd450ebf5bd4540'
  - url: 'https://git.kernel.org/stable/c/67adda7ed5da3e3b64f5b9021a02c21fb374fd9c'
  - url: 'https://git.kernel.org/stable/c/9808ddffb4bc659352df3020cd84d9d864820ee5'
  - url: 'https://git.kernel.org/stable/c/b33f76d33aaeacf3baf3370d8d64985169b36600'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00163
epssPercentile: 0.05937
scores:
  vendor: 5.1
  cna: 7.8
ingestedAt: '2026-09-14T15:23:07.474Z'
---

## Overview

A flaw was found in the Linux kernel's device mapper (dm) array component. Insufficient validation of array block headers during read operations allows a local attacker to craft a malicious on-disk `nr_entries` value. This can lead to an out-of-bounds read from the `dm-bufio` buffer, potentially resulting in memory corruption or information disclosure.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89574.json)

**kernel: dm array: validate array block headers on read** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-18.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

No fix planned:

- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

## Remediation

Out of support scope