F-Secure Virus Descriptions : Music

NAME:	Music
ALIAS:	IWorm_Music, I-Worm.Music

Music is an Internet worm written in Visual Basic that spreads itself as an attachment to e-mail messages. The names of of attachments can be Music.com, Music.exe or Music.zip.

On activation the worm displays a Christmas-related picture and plays a tune as a disguise. Its activation effect usually looks like that:

The messages sent by Music worm have the following subjects and texts:

 Subject: Testing to send file
 Text:    Hi, just testing email using Merry Christmas music file, not bad music.

or:

 Text:    Hi, just testing email using Merry Christmas music file, you'll like it.

The worm has three components: Dropper, Sender and WinSock library.

1. The first worm's component (Dropper) is sent attached to emails. When it is run, it copies itself to Windows system directory with SYSMCM.EXE name and registers this file in auto-run registry key, then plays a tune and displays pictures to disguise itself.

This worm's component doesn't send any messages. To spread further the worm connects two Inet sites and gets the rest of its components from there, copies them to Windows directory with the names: SYSDRV.EXE and SYSTMP.DLL

2. Second worm component (Sender), is downloaded from an Internet website and copied to Windows System directory. It then gets email addresses from Windows Addresss Book and sends infected messages (with Dropper attached) to these addresses.

3. WinSock library is standard MS Visual Studio DLL library that is used to access Windows sockets.

The worm is able to upgrade its components from Internet website: it downloads three files from there (that are supposed to be its plugins), detects their versions, and if these versions are newer than the currently used, the worm replaces its components with new ones. So the worm is able to change its functionality depending on its author needs.

The worm creates new registry key to run itself on each Windows startup:

 HKLM\Software\Microsoft\Windows\CurrentVersion\Run
  SysDrv = %SystemDir%\sysmcm.exe

It also creates one more key where it stores its internal data:

 HKLM\Software\Microsoft\MCM
  FirstRun
  LastRun
  RunMCM
  Status
  SMTP
  Version = 001111

The Sender component code contains the text:

 Hi, tracing this file? It's a very friendly program, it do nothing harm to
 your system.  In fact I hate a file like this, but the bad thing is I cant
 find a job, and I need to rent my basement room, I only hope this file
 could help me to make my both ends meet. Thanks & regards.
 -- The author, Nov 08, 2000.

[Analysis: Eugene Kaspersky, KL; November 2000]