CVE-2026-40393
Mesa WebGPU Out-of-Bounds Memory Access Vulnerability
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.
INFO
Published Date :
April 12, 2026, 7:16 p.m.
Last Modified :
April 16, 2026, 4:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 8254265b-2729-46b6-b9e3-3dfca2d5bfca | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update Mesa to version 25.3.6 or later.
- Update Mesa to version 26.0.1 or later.
- Apply vendor-provided security patches for Mesa.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-40393.
| URL | Resource |
|---|---|
| https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/39866 | Issue Tracking |
| https://lists.freedesktop.org/archives/mesa-dev/2026-February/226597.html | Issue Tracking Mailing List |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-40393 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-40393
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-40393 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-40393 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 16, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:mesa3d:mesa:*:*:*:*:*:*:*:* versions up to (excluding) 25.3.6 *cpe:2.3:a:mesa3d:mesa:26.0.0:*:*:*:*:*:*:* Added Reference Type MITRE: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/39866 Types: Issue Tracking Added Reference Type MITRE: https://lists.freedesktop.org/archives/mesa-dev/2026-February/226597.html Types: Issue Tracking, Mailing List -
New CVE Received by [email protected]
Apr. 12, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-787 Added Reference https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/39866 Added Reference https://lists.freedesktop.org/archives/mesa-dev/2026-February/226597.html