I have a malware called MalSign.Trusops.C4B which is in Program files\file type assistant\tsassist.exe. AVG has secured it and It has one reference to a file/directory and 2 to registry values. I don't know what the malware does, but the registry reference includes 'shared access\parameters\firewallPolicy\standardProfile\authorizedApplications\'. I have searched the web and have not found reference to this particular one, although I have found other MalSign references. Also I am very careful about the web sites I use and don't download from unknown sites so I am wondering where this could have come from. Any ideas?

Thank you