---
id: CVE-2026-63852
title: 'drm/amdgpu/vcn: set no_user_fence for VCN v4.0.3 enc ring'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drm/amdgpu/vcn: set no_user_fence for VCN v4.0.3 enc ring

  VCN encoder and decoder rings do not support 64-bit user fence writes,
  reject CS submissions with user fences…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d <
    c12a5d35033c0640c57c10d7111c010c7b9c2c8e
  - >-
    Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d <
    387b7c7667bd5c53549350ddad866d2fcf75a529
  - >-
    Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d <
    9076a83e5adefd10dc5c967c7b8bde601c4c512a
  - >-
    Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d <
    0177ac6141c8857130cf365369c74dee7b6b1f7f
  - >-
    Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d <
    4532b52b34e4e4310386e6fdf6a643368599f522
  - Linux 6.5
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T15:32:15.463568Z'
published: '2026-07-19'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T20:07:51.529Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-63852'
references:
  - url: 'https://git.kernel.org/stable/c/c12a5d35033c0640c57c10d7111c010c7b9c2c8e'
  - url: 'https://git.kernel.org/stable/c/387b7c7667bd5c53549350ddad866d2fcf75a529'
  - url: 'https://git.kernel.org/stable/c/9076a83e5adefd10dc5c967c7b8bde601c4c512a'
  - url: 'https://git.kernel.org/stable/c/0177ac6141c8857130cf365369c74dee7b6b1f7f'
  - url: 'https://git.kernel.org/stable/c/4532b52b34e4e4310386e6fdf6a643368599f522'
tags:
  - cve.org
epss: 0.00175
epssPercentile: 0.07059
ingestedAt: '2026-10-16T17:24:46.759Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

drm/amdgpu/vcn: set no_user_fence for VCN v4.0.3 enc ring

VCN encoder and decoder rings do not support 64-bit user fence writes,
reject CS submissions with user fences.

(cherry picked from commit ff1a5a125c5a70c328806b9bc01d7d942cf3f9aa)

## Affected

- `Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d < c12a5d35033c0640c57c10d7111c010c7b9c2c8e`
- `Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d < 387b7c7667bd5c53549350ddad866d2fcf75a529`
- `Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d < 9076a83e5adefd10dc5c967c7b8bde601c4c512a`
- `Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d < 0177ac6141c8857130cf365369c74dee7b6b1f7f`
- `Linux >= b889ef4ac98837838c38f7b9f72bba2f33ee367d < 4532b52b34e4e4310386e6fdf6a643368599f522`
- `Linux 6.5`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.