CVE-2026-23338 drm/amdgpu/userq: Do not allow userspace to trivially triger kernel warnings

What is CVE-2026-23338?

CVE-2026-23338 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Mar 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/userq: Do not allow userspace to trivially triger kernel warnings

Userspace can either deliberately pass in the too small num_fences, or the required number can legitimately grow between the two calls to the userq wait ioctl. In both cases we do not want the emit the kernel warning backtrace since nothing is wrong with the kernel and userspace will simply get an errno reported back. So lets simply drop the WARN_ONs.

(cherry picked from commit 2c333ea579de6cc20ea7bc50e9595ef72863e65c)

Which versions are affected by CVE-2026-23338?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-23338?

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-2026-23338 being exploited?

There is no known exploitation of CVE-2026-23338 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-23338, DEBIAN-CVE-2026-23338, GHSA-ggpq-p67g-h639, UBUNTU-CVE-2026-23338.