CVE-2026-40393
CRITICALCVSS 9.8/10EPSS 0.35%
Last modified
CVE-2026-40393 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 0.35% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mesa3d | Mesa | < 25.3.6 |
| Mesa3d | Mesa | 26.0.0 |
References
- https://lists.freedesktop.org/archives/mesa-dev/2026-February/226597.htmlIssue Tracking, Mailing List
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-40393?
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.
How severe is CVE-2026-40393?
CVE-2026-40393 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.35% probability of exploitation in the next 30 days.
How do I fix CVE-2026-40393?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
Are you affected by CVE-2026-40393?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST