url:mal keeps popping up

Viruses and worms
1

how do I get rid of this? it keeps popping up every few seconds.

avast!web shield has blocked a harmful webpage or file.
object: http://4ster.com/task/2/
infection: url:mal
process: c:\windows\system32\svchost.exe

2

https://forum.avast.com/index.php?topic=53253.0

3

Monitoring.