W32/Sobig.C Worm

 Information about the W32/Sobig.C worm:

W32/Sobig.C is an email worm. It is a variant of W32/Sobig.A. This worm will infect Windows systems. The worm spreads through email and shared drives on network.

The worm arrives with the infected email having the from address as bill@microsoft.com or any random address . The subject of the infected mail will be any one of the following;

Approved
Re: 45443-343556
Re: Application
Re: Approved
Re: Movie
Re: Submited (004756-3463)
Re: Your application Re: Your Screensaver

The content of the mail will be;

Please see the attached file.

The infected attachment will have any one of the following names;

submited.pif
screensaver.scr
movie.pif
documents.pif
document.pif
approved.pif
application.pif
45443.pif

When the infected attachment is executed, the worm copies itself as mscvb32.exe under the Windows folder. The worm modifies registry at the following location to run itself at the startup.

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run

The worm attempts to find the shared resources on the network and tries to copy itself under the following folders of the target system;

Windows\All Users\Start Menu\Programs\StartUp\
Documents and Settings\All Users\Start Menu\Programs\Startup

The worm tries to collect all the email addresses found in the files having the following extensions;

.dbx
.eml
.htm
.html
.txt
.wab

The worm tries to mail itself to these email addresses using its own SMTP engine.

This worm first appeared on 31st May 2003.

 Other names of W32/Sobig.C worm:

This worm is also known as Sobig.C, W32/Sobig.c@MM , W32.Sobig.C@mm