---
id: CVE-2026-98546
title: >-
  kernel: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2
  (CVE-2026-98546)
summary: >-
  A flaw was found in the Linux kernel's ARM64 architecture support. When
  user-space access to performance monitoring counters is enabled, write traps
  for a write-only performance register are improperly configured during
  hypervisor initiali…
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-617
vendor: Red Hat
product: Linux
affected:
  - >-
    Linux >= 686d8f7b592f3466f44aea653c8147611b351c83 <
    bb8c90c86441c090e9036f019cf1b4d7894a2c40
  - >-
    Linux >= 858c7bfcb35e1100b58bb63c9f562d86e09418d9 <
    071f51188a5d8ec10535541255587976d12fc7d8
  - >-
    Linux >= 858c7bfcb35e1100b58bb63c9f562d86e09418d9 <
    ce71865bf43f88bed9d9218e9218e537150be506
  - >-
    Linux >= 858c7bfcb35e1100b58bb63c9f562d86e09418d9 <
    2bc6b218717b9d08f466f88209251d54bc09b207
  - Linux 882f78400322c0aec4b641a7168adad9a66bc0c2
  - Linux >= 6.12.25 < 6.12.112
  - Linux >= 6.14.4 < 6.15
  - Linux 6.15
published: '2026-10-18'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T00:14:26+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98546.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98546.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98546'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2554987'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98546'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98546'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98546.mbox
  - url: 'https://git.kernel.org/stable/c/bb8c90c86441c090e9036f019cf1b4d7894a2c40'
  - url: 'https://git.kernel.org/stable/c/071f51188a5d8ec10535541255587976d12fc7d8'
  - url: 'https://git.kernel.org/stable/c/ce71865bf43f88bed9d9218e9218e537150be506'
  - url: 'https://git.kernel.org/stable/c/2bc6b218717b9d08f466f88209251d54bc09b207'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.002
epssPercentile: 0.0978
ingestedAt: '2026-10-18T15:45:12.266Z'
---

## Overview

A flaw was found in the Linux kernel's ARM64 architecture support. When user-space access to performance monitoring counters is enabled, write traps for a write-only performance register are improperly configured during hypervisor initialization. A local user can exploit this vulnerability by issuing a write to this register, triggering an unhandled hypervisor exception that leads to a Denial of Service (DoS) through a host system crash.

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98546.json)

**kernel: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-20.

Not 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

## Remediation

Refer to the advisory for fix availability.