CVE-2023-53552: 
Linux Kernel vulnerability analysis and mitigation

A use-after-free vulnerability was discovered in the Linux kernel's DRM/i915 driver component, identified as CVE-2023-53552. The vulnerability relates to how references to i915requests may be trapped by userspace inside a syncfile or dmabuf (dma-resv) and held indefinitely across different processes (NVD). The issue was disclosed on October 4, 2025.

The vulnerability occurs in the DRM/i915 driver's handling of GuC virtual engines. To counter memory leaks, the system tries not to keep references from the request past their completion. However, on fence release, the system needs to verify if rq->engine is valid and points to a hardware engine. The fix involved adding an extra bit to rq->execution_mask for marking virtual engines (RedHat). The vulnerability has been assigned a CVSS v3.1 base score of 7.0 with vector AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

The vulnerability could potentially lead to use-after-free conditions in the Linux kernel's DRM/i915 driver, which could result in memory corruption, system crashes, or potential privilege escalation. This affects systems using Intel graphics with the i915 driver (RedHat).

The vulnerability has been patched in the Linux kernel. The fix involves marking requests for GuC virtual engines to avoid use-after-free conditions by adding an extra bit to rq->execution_mask (Ubuntu). Users are advised to update their systems to the patched kernel version.