CVE-2026-63849

A flaw was found in the Linux kernel's AMD GPU (Graphics Processing Unit) Video Core Next (VCN) component. This vulnerability arises because the VCN encoder and decoder rings do not properly support 64-bit user fence writes. A local attacker could potentially exploit this by submitting command streams (CS) with user fences, leading to the rejection of these submissions. This could result in a denial of service, preventing legitimate operations of the VCN component.

This vulnerability is rated as having a Low impact because exploitation requires local authenticated access and is strictly limited to systems equipped with specialized AMD graphics hardware featuring Video Core Next (VCN) v5.0.1. Standard Red Hat Enterprise Linux server deployments typically do not utilize this specific consumer graphics hardware block. Furthermore, the issue only affects multimedia processing rings, causing submission rejections without compromising host data confidentiality or system 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.