My machine had this symptom for quite a while. It popped up every a few hours and taking much of the CPU resource. I end up need to terminate the process from the Task Manager every time. Scanning by Avira and MalwareByte AntiMalware did not really resolve this problem. Until yesterday I found a forum thread dropping a little hint that Avast may resolve the problem.
It did! I had uninstalled my Avira and installing back Avast on my machine. It detected C:\WINDOWS\system32\autorun.wsh as a virus with High severity. See http://www.exterminate-it.com/malpedia/file/autorun.wsh. Hope this will help someone.