Improper input validation in Linux kernel - CVE-2026-63854
Published: July 20, 2026
Vulnerability identifier: #VU138795
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-63854
CWE-ID: CWE-20
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper input validation in the amdgpu vcn v3.0 encoder and decoder rings when processing command submission requests with user fences. A local user can submit a crafted command stream with a user fence to cause a denial of service.
The issue affects VCN v3.0 encoder and decoder rings that do not support 64-bit user fence writes.
How to mitigate CVE-2026-63854
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/26c4f38529ac78930c9c4713e16ebc5b689bb0a3
- https://git.kernel.org/stable/c/2d6525e7b2504f5bbfe9417cddc1e8da858791dd
- https://git.kernel.org/stable/c/b076e45e6f757a2829e80d0144c1b5f201bee5af
- https://git.kernel.org/stable/c/e74fc9c72c1ba78d0de0b849f5929c3b39a8e20c
- https://git.kernel.org/stable/c/f1e5a6660d7cbf006079126d9babbf0ccf538c6b