Executive brief
A vulnerability in the AMD display driver for the Linux kernel can cause the system to hang or become unresponsive. This occurs due to a logic error in how the hardware locking mechanism is managed during certain display update sequences. An exploit could lead to a denial-of-service, impacting system availability and operational stability.
Technical details
A vulnerability exists in the Linux kernel's AMD display driver (drm/amd/display) within the Hardware Sequencer (HWSS) fast path. The root cause is a mismatched unlock logic for the Display Microcontroller Unit (DMUB) hardware lock. Specifically, the evaluation criteria for acquiring the lock differed from the criteria for releasing it, leading to a permanent hang on ASICs without Firmware Assisted Mode Switch (FAMS) support. An attacker with local access could potentially trigger this condition during display state changes, resulting in a denial-of-service (kernel hang). The fix involves synchronizing the lock/unlock logic using a persistent flag.
Affected products
- Linux Linux Kernel All versions prior to fixed commits in 2026
Timeline
- 2025-12-08: other: Patch authored by Nicholas Kazlauskas
- 2026-05-08: disclosed: CVE published by kernel.org
- 2026-05-08: advisory: NVD record created