Windows Defender Antivirus detects and removes this threat. 

This threat can give a malicious hacker access to your PC.

It spreads via removable drives and Windows Live Messenger.

Win32/Phorpiex is a family of worms that spread via removable drives and IM (instant messaging) software. The worms also allow backdoor access and control.

Worm:Win32/Phorpiex.A is a worm that spreads via removable drives and Windows Live Messenger. It allows an attacker to gain backdoor access and control of your computer.

Worm:Win32/Phorpiex.O is a worm that downloads other files which may be detected as malware. The worm spreads via instant messaging software, such as Google Talk, ICQ, Paltalk, Skype, Windows Live Messenger and Xfire. 

You may unknowingly download the worm, thinking it is something else.

It is a member of the Win32/Phorpiex family of worms.

Worm:Win32/Phorpiex.M is a worm that spreads via removable drives, fixed drives, and email. It lets a remote attacker gain access and control of your computer.