---
id: CVE-2026-98476
title: >-
  kernel: s390/cio: Fix NULL pointer dereference in ccw_device_get_util_str()
  (CVE-2026-98476)
summary: >-
  A flaw was found in the Linux kernel's s390 channel I/O (CIO) subsystem. When
  querying device utility strings, the kernel fails to verify that an associated
  channel path remains valid after its removal from the registry. A local user
  could…
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/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 9
  - openshift_container_platform 4
published: '2026-10-18'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T11:13:57+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98476.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98476.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98476'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2554875'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98476'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98476'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98476.mbox
  - url: 'https://git.kernel.org/stable/c/9d8b21820caed9128945fffcedf03e2a4c21eee2'
  - url: 'https://git.kernel.org/stable/c/5fc54e04dad90b15d0430118b3f288a1d64e66c9'
  - url: 'https://git.kernel.org/stable/c/27e396a89f76f742abdbe9f8c4a58a6e806fdf59'
  - url: 'https://git.kernel.org/stable/c/dbf30e661ceb9a52c94c85719716391dcc29142a'
  - url: 'https://git.kernel.org/stable/c/5e006ac90a4d331db1dd712b91fec849b45ffc01'
  - url: 'https://git.kernel.org/stable/c/c3bbcb32deecc06ebb1762398399b566d5ff2fc9'
  - url: 'https://git.kernel.org/stable/c/44b16b02608058fc72198ac0205969f0f43065df'
  - url: 'https://git.kernel.org/stable/c/5b76268dac968612f7283d59b539036de955b7d9'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00177
epssPercentile: 0.07147
ingestedAt: '2026-10-18T15:45:12.298Z'
---

## Overview

A flaw was found in the Linux kernel's s390 channel I/O (CIO) subsystem. When querying device utility strings, the kernel fails to verify that an associated channel path remains valid after its removal from the registry. A local user could exploit this condition during hardware reconfiguration, resulting in a NULL pointer dereference that causes a system crash and Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98476.json)

**kernel: s390/cio: Fix NULL pointer dereference in ccw_device_get_util_str()** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-20.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

No fix planned:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

Not affected:

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

## Remediation

Fix deferred