The main feature on software is the reutilization of components and this ancient bug was discovered by Google security researcher Tavis Ormandy in January 2010 and involves a utility that allows newer versions of Windows to run very old programs.
Mr Ormandy has found a way to exploit this utility in Windows XP, Windows Server 2003 and 2008 as well as Windows Vista and Windows 7.
You can read more on BBC article: Microsoft to patch 17-year-old computer bug