CVE-2026-85921: Windows Secure Kernel Mode Elevation of Privilege Vulnerability

Overview

Severity

High (CVSS 8.2)

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Elevation of Privilege

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Sep

Released

2026-09-14

Description

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

FAQ

What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain Virtual Trust Level 1 (VTL1) privileges.

Affected Products (2)

Windows

• Windows 11 version 26H1 for x64-based Systems
• Windows 11 Version 26H1 for ARM64-based Systems

Security Updates (1)

• 5129194

Revision History

• 2026-09-14: Information published.