GEN:SID 1:208
Message BACKDOOR PhaseZero Server Active on Network
Summary Phase0 is a Trojan Horse offering the attacker control of the victim
host. This event is generated when the victim server replies to an
attackers client connection request.
Impact Possible theft of data and control of the targeted machine leading to a
compromise of all resources the machine is connected to. This Trojan
also has the ability to delete data, steal passwords and disable the
machine.
Detailed Information This Trojan affects the following operating systems:

    Windows 95
    Windows 98
    Windows ME
    Windows NT
    Windows 2000

The Trojan changes system registry settings to add the PhaseZero server
to programs normally started on boot. Due to the nature of this Trojan
it is unlikely that the attacker's client IP address has been spoofed.

The default name of the server application is MsgServ.

Server Port: 555 although this can be changed.
Affected Systems  
Attack Scenarios This Trojan may be delivered to the target in a number of ways. This
event is indicative of an existing infection being activated. Initial
compromise can be in the form of a Win32 installation program that may
use the extension ".jpg" or ".bmp" when delivered via e-mail for
example.
Ease of Attack This is Trojan activity, the target machine may already be compromised.
Updated virus definition files are essential in detecting this Trojan.
Corrective Action Edit the system registry to remove the extra keys or restore a
previously known good copy of the registry.

Affected registry keys are:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\

Registry keys added:

    MsgServ

Delete the server program msgsvr32.exe and/or ServerS.exe.

A reboot of the infected machine is recommended.
Additional References Dark-e
http://www.dark-e.com/archive/trojans/phase/