---
id: CVE-2026-80689
title: >-
  kernel: tracing/mmiotrace: Add NULL check for mmio_trace_array in logging
  functions (CVE-2026-80689)
summary: >-
  A flaw was found in the Linux kernel's mmiotrace component. When the
  `mmio_trace_array` is not initialized or is disabled, invoking
  `mmio_trace_rw()` or `mmio_trace_mapping()` can lead to a NULL pointer
  dereference. This can cause a system…
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-476
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
published: '2026-08-28'
updated: '2026-10-17'
sourceUpdated: '2026-10-17T21:45:56+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80689.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80689.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-80689'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2525375'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-80689'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80689'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026082803-CVE-2026-80689-f3d3@gregkh/T
  - url: 'https://git.kernel.org/stable/c/dc1b1a057b3bb901f83433700e604fe0ae67c5f2'
  - url: 'https://git.kernel.org/stable/c/6aee2d478545c089dd5d055d3c9f0c7ea034fb80'
  - url: 'https://git.kernel.org/stable/c/4e4ab09db7899d7f2d2293a18adf0fa200a27e73'
  - url: 'https://git.kernel.org/stable/c/2df964d141270c40f07547b0c2e0a51e2573d46d'
  - url: 'https://git.kernel.org/stable/c/876014b4eeb927146430e7591cf959a7ceb8d64a'
  - url: 'https://git.kernel.org/stable/c/a20a0010eb6485f60cd64e15ebc85a4bd388642e'
  - url: 'https://git.kernel.org/stable/c/60234845142fddb27db89ebc00a65178421fb3a4'
  - url: 'https://git.kernel.org/stable/c/12b80cdbc54cf615b4717a4e8180063408091ea2'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00177
epssPercentile: 0.07181
ingestedAt: '2026-09-14T15:23:07.456Z'
---

## Overview

A flaw was found in the Linux kernel's mmiotrace component. When the `mmio_trace_array` is not initialized or is disabled, invoking `mmio_trace_rw()` or `mmio_trace_mapping()` can lead to a NULL pointer dereference. This can cause a system crash, resulting in a Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Low · 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 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80689.json)

**kernel: tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functions** — rated Low by Red Hat. Released 2026-08-28, updated 2026-10-17.

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

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

## Remediation

Out of support scope

Workarounds / mitigations:

- 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.