Zlob fake codec has been update. It drops the following file:
%SYSTEM%\hkushdr.dll
[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\SharedTaskScheduler]
"{d1577581-2ed7-469f-99b1-72c1339e0ee0}"="doctordom"
It also installs Toolbar, BHO, Antispycheck Rogue software...
SmitfraudFix removes the infection.