This bug uses two BUG_ON assertions in the AMDGPU driver to verify that a fence writeback address is dword‑aligned. The condition can be reached by an unprivileged user space process that submits a crafted DRM_IOCTL_AMDGPU_CS command. When the misaligned address is detected the kernel panics, taking the host system offline and resulting in a denial of service. The intent of the original code was to signal a driver bug; however, allowing a user to trigger a crash was an inappropriate response. Replacing the assertions with WARN_ON logs the issue without taking the system down.

All Linux kernel releases that contain the older AMDGPU SDMA4 code before the patch are affected. Linux kernel users with the AMDGPU driver installed could exploit the flaw through the DRM interface; no specific kernel version range was supplied by the CNA. It is inferred that these older releases are affected, as no explicit version range is provided.

The vulnerability is exploitable by any unprivileged user with write access to the DRM device that can submit CS commands. Because it leads only to a kernel panic and does not provide code execution or data exfiltration, the impact is limited to denial of service. The CVSS score is 5.5, indicating moderate severity. No public exploit is known at this time. The EPSS score is less than 1%, indicating a very low exploit probability, and the issue is not listed in CISA’s KEV catalog.