CVE-2026-40393 Memory corruption in Mesa

High 8.1 Published 12 Apr 2026 Updated 13 Jul 2026

Out-of-bounds memory access in Mesa's WebGPU implementation allows attackers to cause crashes or execute arbitrary code via untrusted data sizes.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-40393?

CVE-2026-40393 is a high-severity memory corruption vulnerability in mesa3d Mesa, published on 12 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In Mesa before 25.3.6 and 26 before 26.0.1, out-of-bounds memory access can occur in WebGPU because the amount of to-be-allocated data depends on an untrusted party, and is then used for alloca.

Weakness: CWE-787

Which versions are affected by CVE-2026-40393?

It affects 1 product.

Linux distribution packages (1)

Mesa SUSE:Linux Enterprise Micro 5.2 All versions 20.2.4-150300.59.12.1

Products include Mesa3d Mesa.

How do I fix CVE-2026-40393?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-40393 being exploited?

There is no known exploitation of CVE-2026-40393 in the wild and no public exploit code.

Sources

Also known as AZL-82688, BELL-CVE-2026-40393, CLSA-2026-1787314086, DEBIAN-CVE-2026-40393, ECHO-970d-b2f9-098e, GHSA-w54f-pw7x-c532 and 17 more.