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CVE-2026-40403

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Moole Vulnerability Database

Find real vulnerabilities before they ship

Vulnerability Database › CVE-2026-40403

High

CVE-2026-40403

Heap-based buffer overflow in Windows Win32K - GRFX allows an authorized attacker to execute code locally.

VectorLOCAL

PublishedMay 12, 2026, 18:17

Published Bysecure@microsoft.com

Base Score

Score8.8

Affected Versions

No affected versions found.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40403

Weakness Type

CWE-122

CVSS Metrics

Base Score

8.8

Vector String

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Base SeverityHigh

Version

3.1

Attack Vector (AV)

LOCAL