MicrosoftCVE-2026-85921

Microsoft Windows 11 version 26H1: double free

High8.2CVE-2026-85921 · Published Sep 14, 2026 · updated Sep 16, 2026

Double free in Windows Secure Kernel Mode allows an authorized attacker to elevate privileges locally.

Microsoft advisory

Affected versions

Package	Affected	Fixed in
Windows 11 version 26H1 Product	>= 10.0.28000.0, < 10.0.28000.2956	10.0.28000.2956

Details and references

CVSS 3.1: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Severity from: the vendor (its own CVE record or advisory)
Weakness: CWE-415

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