Troj_Zlob.BFE is a Trojan that may be dropped or downloaded from a remote site by other malware. It may also be downloaded unknowingly by a user while visiting malicious Web sites.

Upon execution, it connects to a certain URL to download and execute a file detected by Trend Micro as TROJ_AGENT.RFR. As a result, malicious routines of the downloaded Trojan are exhibited on the affected system.

Technical details can be found at this Trend Micro page.