Secure Boot Security Feature Bypass Vulnerability

Improper access control in Windows Secure Boot allows an authorized attacker to bypass a security feature locally.

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7.9CVSS out of 10High severity

Scope

What the vendor says is affected

Windows 11 version 26H1 for x64-based Systems
Windows 11 Version 26H1 for ARM64-based Systems
Windows Server 2025 (Server Core installation)
Windows 11 Version 25H2 for ARM64-based Systems
Windows 11 Version 25H2 for x64-based Systems
Windows 11 Version 24H2 for ARM64-based Systems
Windows 11 Version 24H2 for x64-based Systems
Windows Server 2025

Versions the vendor lists as fixed

10.0.28000.2269
10.0.26100.32995
10.0.26200.8655
10.0.26100.8655

Next step

What the vendor recommends

Install KB5095051. Install KB5094125. Install KB5094126.

Review the complete instructions on the vendor's site

Timeline

When this advisory changed

Jun 9, 2026 at 7:00 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Sep 28, 2026 at 11:20 AM UTC
Added to SecurityAlert
We collected the advisory from the official source.

Vulnerabilities

CVEs named in this advisory

CVE-2026-45654View CVSS, KEV, EPSS, and threat context

Source

Start with the vendor's bulletin

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-45654
Last source check: Sep 28, 2026 at 11:20 AM UTC

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What the vendor says is affected

Versions the vendor lists as fixed

What the vendor recommends

When this advisory changed

CVEs named in this advisory

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