The Installer in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, and 1607, and Windows Server 2016 mishandles library loading, which allows local users to gain privileges via a crafted application, aka "Windows Installer Elevation of Privilege Vulnerability."
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-149