---
id: CVE-2026-85921
title: >-
  Double free in Windows Secure Kernel Mode allows an authorized attacker to
  elevate privileges locally.
summary: >-
  Double free in Windows Secure Kernel Mode allows an authorized attacker to
  elevate privileges locally.
severity: high
cvss: 8.2
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H'
cwe:
  - CWE-415
vendor: Microsoft
product: Windows 11 version 26H1
affected:
  - windows_11_version_26h1 >= 10.0.28000.0 < 10.0.28000.2956
published: '2026-09-14'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:30:49.967'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85921'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85921'
    label: secure@microsoft.com
tags:
  - nvd
  - cve.org
epss: 0.00356
epssPercentile: 0.26679
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-14T19:11:21.507210Z'
ingestedAt: '2026-09-14T19:13:23.460Z'
---

## Overview

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

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.