Win32/Gapz: New Bootkit Technique : http://www.welivesecurity.com/2012/12/27/win32gapz-new-bootkit-technique/
In the last couple of years a number of new bootkits have appeared in the wild targeting the Microsoft Windows platform. Among the most prominent examples are TDL4, Olmasco and Rovnix. These each employ different ways of infecting the system by means of modifying either the MBR (Master Boot Record) or the VBR/IPL (Volume Boot Record/Initial Program Loader). This is shown in the figure below.