CVE-2026-43398 drm/amdgpu: add upper bound check on user inputs in wait ioctl
A missing upper bound check in the amdgpu wait ioctl allows local attackers to trigger an out-of-memory condition, causing a denial of service.
- 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-2026-43398?
CVE-2026-43398 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 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/amdgpu: add upper bound check on user inputs in wait ioctl
Huge input values in amdgpu_userq_wait_ioctl can lead to a OOM and could be exploited.
So check these input value against AMDGPU_USERQ_MAX_HANDLES which is big enough value for genuine use cases and could potentially avoid OOM.
v2: squash in Srini's fix
(cherry picked from commit fcec012c664247531aed3e662f4280ff804d1476)
Which versions are affected by CVE-2026-43398?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43398?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-43398 being exploited?
There is no known exploitation of CVE-2026-43398 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-86196, BELL-CVE-2026-43398, DEBIAN-CVE-2026-43398, GHSA-wv9h-grcg-85wc, ROOT-OS-UBUNTU-2204-CVE-2026-43398, ROOT-OS-UBUNTU-2404-CVE-2026-43398 and 1 more.