In particular, the Trojan establish unauthorized connection to remote server to fetch other components, receive new tasks and reports infection status and collected confidential such as log-in accounts and banking details. And it will overwrite itself into C:\Windows\System32\services.exe once the malicious program is launched.Many users have difficulties to run Windows update and Firewall with this Trojan. At the same time, the browser seems to be manipulated since it’s constantly redirected to several irrelevant pages. Besides, Sirefef!cfg tries to block removal attempt by searching for and cancelling the program’s processes and the computer will become severely corrupted in that way. Thus user need to get rid of Sirefef!cfg Trojan once upon the detection.