Microsoft Security Response CenterCVE-2026-45641

Windows Hyper-V Remote Code Execution Vulnerability

Access of resource using incompatible type ('type confusion') in Windows Hyper-V allows an unauthorized attacker to execute code locally.

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8.4CVSS out of 10Critical severity

Scope

What the vendor says is affected

Windows Server 2022
Windows Server 2022 (Server Core installation)
Windows 10 Version 21H2 for x64-based Systems
Windows 10 Version 22H2 for x64-based Systems
Windows Server 2025 (Server Core installation)
Windows 11 Version 25H2 for x64-based Systems
Windows 11 Version 23H2 for x64-based Systems
Windows 11 Version 24H2 for x64-based Systems
Windows Server 2025
Windows 11 version 26H1 for x64-based Systems

Versions the vendor lists as fixed

10.0.20348.5256
10.0.19044.7417
10.0.19045.7417
10.0.26100.32995
10.0.26200.8655
10.0.22631.7219
10.0.26100.8655
10.0.28000.2269

Next step

What the vendor recommends

Install KB5094128. Install KB5094127. Install KB5094125. Install KB5094126. Install KB5093998. Install KB5095051.

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-2026-45641View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-45641
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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