Critical severity · published Apr 12, 2026
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…
9.8
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ME
Mesa · mesa3d
before 25.3.6; 26.0.0 before 26.0.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40393
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40393
Issue Tracking
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/39866
Issue Tracking
https://lists.freedesktop.org/archives/mesa-dev/2026-February/226597.html
lists.debian.org
https://lists.debian.org/debian-lts-announce/2026/07/msg00021.html
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