An information disclosure vulnerability exists when Windows Hyper-V on a host operating system fails to properly validate input from an authenticated user on a guest operating system, aka "Windows Hyper-V Information Disclosure Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8434