---
id: CVE-2026-64524
title: >-
  kernel: drm/hyperv: validate resolution_count and fix WIN8 fallback
  (CVE-2026-64524)
summary: >-
  A flaw was found in the Linux kernel's `drm/hyperv` component. A malicious
  Hyper-V guest could exploit an out-of-bounds memory access vulnerability by
  sending a crafted resolution response. This could potentially lead to
  information disclo…
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 9
published: '2026-07-25'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T11:18:30+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64524.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64524.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-64524'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2507029'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-64524'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64524'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026072533-CVE-2026-64524-0002@gregkh/T
  - url: 'https://git.kernel.org/stable/c/96f7de3172d4aa878b7f87173b2b3507c350fcd6'
  - url: 'https://git.kernel.org/stable/c/bc573752f3dac0d1ab8df7078c1851bc76717653'
  - url: 'https://git.kernel.org/stable/c/1fb565b77b8f44afabb02de6310065f109d89e94'
  - url: 'https://git.kernel.org/stable/c/a321c908f2eeea01539668eb270d074d9b88e490'
  - url: 'https://git.kernel.org/stable/c/9c698b2c43c2667c34f5336bf46ad5786216ac2a'
  - url: 'https://git.kernel.org/stable/c/8a114b25b5521eae451b13bce98ae978624962e5'
  - url: 'https://git.kernel.org/stable/c/13d33b9ef67066c77c84273fac5a1d3fde3533d1'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00142
epssPercentile: 0.03516
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-16T15:41:39.558295Z'
scores:
  vendor: 5.5
  cna: 7.7
ingestedAt: '2026-10-16T17:24:46.825Z'
---

## Overview

A flaw was found in the Linux kernel's `drm/hyperv` component. A malicious Hyper-V guest could exploit an out-of-bounds memory access vulnerability by sending a crafted resolution response. This could potentially lead to information disclosure or a denial of service. Additionally, an issue with the resolution probe fallback mechanism could prevent display functionality from initializing correctly, resulting in a denial of service.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64524.json)

**kernel: drm/hyperv: validate resolution_count and fix WIN8 fallback** — rated Moderate by Red Hat. Released 2026-07-25, updated 2026-10-23.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9

No fix planned:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9

Not affected:

- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8

## Remediation

Fix deferred