Troj/Bdoor-BX is a Trojan for the Windows platform that contains backdoor functions that allow unauthorised remote access to the infected computer via IRC channels.
When run Troj/Bdoor-BX copies itself to the Windows system folder as WINLGON.EXE and creates the following registry so as to run itself automatically on computer logon:
HKLM\Software\Microsoft\Windows\CurrentVersion\Run
.service
%SYSTEM%\winlgon.exe
Once installed, Troj/Bdoor-BX will connect to an IRC server and listen for backdoor commands.
The Trojan has the capability to download and run files from the internet and setup more listening ports when instructed to do so by a remote attacker.