CVE-2026-89816 drm: Fix drm_crtc_commit leak if signaled when PAGE_FLIP_EVENT is used
A memory leak in the Linux kernel DRM subsystem allows local attackers to cause denial of service by triggering specific page flip events.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89816?
CVE-2026-89816 is a memory corruption vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
drm: Fix drm_crtc_commit leak if signaled when PAGE_FLIP_EVENT is used
Commit 1c6ceeee6ebb ("drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits") fixed a very similar issue when the event was allocated by drm_atomic_helper_setup_commit() itself.
However, if the event is allocated in prepare_signaling(), it will also be set to NULL in complete_signaling(), which prevents drm_crtc_commit from being put in __drm_atomic_helper_crtc_destroy_state().
Dropping the reference when the event is set to NULL at complete_signaling() fixes the leak.
The leak can be reproduced by sending a signal to the thread using DRM_MODE_PAGE_FLIP_EVENT and using a sw_sync fence to cause the atomic ioctl to block at drm_atomic_helper_wait_for_fences(). It happened both with amdgpu and vkms.
Which versions are affected by CVE-2026-89816?
How do I fix CVE-2026-89816?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-89816 being exploited?
There is no known exploitation of CVE-2026-89816 in the wild and no public exploit code.
Sources
Also known as AZL-101247, BELL-CVE-2026-89816, DEBIAN-CVE-2026-89816, GHSA-6f96-mhg4-cfw6, UBUNTU-CVE-2026-89816.