CVE-2026-63850

A flaw was found in the Linux kernel's AMDGPU Video Core Next (VCN) component. The VCN encoder and decoder rings, specifically version 5.0.0, do not correctly support 64-bit user fence writes. This can lead to a denial of service, as the kernel will reject command submissions that attempt to use these unsupported user fences, preventing affected applications from utilizing the VCN functionality as intended.

This vulnerability is rated as Moderate impact because successful exploitation requires local user access and is restricted to systems equipped with AMD graphics processors featuring Video Core Next (VCN) 5.0. On typical Red Hat Enterprise Linux deployments lacking this specific graphics hardware, or where multimedia hardware acceleration is not in use, exposure is not present. On systems with vulnerable hardware, a local user could submit malformed fence commands to disrupt video processing services, resulting in a denial of service without compromising system confidentiality or integrity.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.