CVE-2026-85921: Microsoft Windows 11 26h1

High severity, CVSS 8.2. EPSS: 0.3% chance of exploitation in the next 30 days.

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

Affected products

• Microsoft Windows 11 26h1: before 10.0.28000.2956 (fixed in 10.0.28000.2956)

Published 2026-09-14. Last modified 2026-09-29.