Linux aws: In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: zero-initialize GART table on allocation GART TLB is flushed after… (CVE-2026-53374)

The Linux kernel AMDGPU driver had a vulnerability where the GART table was not zero-initialized on allocation, leading to speculative loading of uninitialized page table entries (PTEs) from the same cacheline. This could cause the GPU to use stale or garbage PTEs from the TLB, potentially impacting system integrity. The fix involves zero-initializing the GART table with memset_io() immediately after allocation to ensure no stale entries are used. This vulnerability is tracked as CVE-2026-53374 and affects linux-aws kernel versions prior to 6.8.0-1061.64~22.04.1 and similar builds. The patch is available and included in updated kernel packages.

If exploited, this vulnerability could allow the GPU to use stale or garbage page table entries, potentially leading to incorrect GPU memory accesses or corruption. The CVSS score of 8.8 indicates a high severity with potential for significant confidentiality, integrity, and availability impact. However, no known exploits are reported in the wild. The vulnerability requires local privileges and low complexity to exploit.

A patch is available for this vulnerability. Users should update their linux-aws kernel packages to versions 6.8.0-1061.64~22.04.1 or later as provided by their vendor. After updating, a system reboot is required to apply the fix. Due to ABI changes, recompilation and reinstallation of third-party kernel modules may be necessary. Follow vendor instructions for updating and rebuilding kernel modules.