Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, Windows 8.1,and Windows Server 2012 R2 systems running Microsoft's IIS web server are affected. The component at fault is HTTP.sys, a kernel-level driver that forwards requests for webpages and the like to the user-space server software, and caches static files.
I present a way to check for the exploit -