Microsoft Security Response CenterCVE-2026-42972

Windows Hyper-V Information Disclosure Vulnerability

Exposure of sensitive information to an unauthorized actor in Windows Hyper-V allows an authorized attacker to disclose information locally.

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5.5CVSS out of 10High severity

Scope

What the vendor says is affected

Windows 10 Version 1809 for x64-based Systems
Windows Server 2019
Windows Server 2019 (Server Core installation)
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 ARM64-based Systems
Windows 11 Version 25H2 for x64-based Systems
Windows 11 Version 23H2 for ARM64-based Systems
Windows 11 Version 23H2 for x64-based Systems
Windows 11 Version 24H2 for ARM64-based Systems
Windows 11 Version 24H2 for x64-based Systems
Windows Server 2025
Windows 10 Version 1607 for x64-based Systems
Windows Server 2016
Windows Server 2016 (Server Core installation)
Windows Server 2012
Windows Server 2012 (Server Core installation)
Windows Server 2012 R2
Windows Server 2012 R2 (Server Core installation)
Windows 11 Version 26H1 for ARM64-based Systems
Windows 11 version 26H1 for x64-based Systems

Versions the vendor lists as fixed

10.0.17763.8880
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
10.0.14393.9234
6.2.9200.26132
6.3.9600.23228
10.0.28000.2269

Next step

What the vendor recommends

Install KB5094123. Install KB5094128. Install KB5094127. Install KB5094125. Install KB5094126. Install KB5093998. Install KB5094122. Install KB5094042. Install KB5094041. 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-2026-42972View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-42972
Last source check: Sep 28, 2026 at 11:20 AM UTC

Open the official bulletin How SecurityAlert builds this record

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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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