MSRC-CVE-2026-20825 — Windows Hyper-V Information Disclosure Vulnerability

Summary

Impact: Information Disclosure. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

What type of information could be disclosed by this vulnerability?
The type of information that could be disclosed if an attacker successfully exploited this vulnerability is Guest VM to Hyper-V host server - virtualization security boundary.

Security updates
10.0.17763.8276 — https://support.microsoft.com/help/5073723
10.0.20348.4648 — https://support.microsoft.com/help/5073457
10.0.19044.6809 — https://support.microsoft.com/help/5073724
10.0.26100.32230 — https://support.microsoft.com/en-us/topic/a6021fd2-b3b7-45a7-b68e-35c28a2a77da
10.0.26200.7623 — https://support.microsoft.com/help/5074109
10.0.22631.6491 — https://support.microsoft.com/help/5073455
10.0.25398.2092 — https://support.microsoft.com/help/5073450

Vulnerabilities 1

Medium 4.4

CVE-2026-20825

Windows Hyper-V Information Disclosure Vulnerability

Improper access control in Windows Hyper-V allows an authorized attacker to disclose information locally.

Microsoft Windows Server 2019 Windows Server 2019 (Server Core installation) Windows 10 Version 1809 Windows

Jan 13, 2026

Revision history

2026-01-13 #1
Information published.

References

CVE-2026-20825 Windows Hyper-V Information Disclosure Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20825
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss