Email-Worm.Win32.3DStars

Technical Details

This is an Internet worm that spreads via e-mail as an attached EXE file. The worm itself is a Win32 executable file about 70Kb in length, and written in VisualBasic. The worm has many bugs, and in many cases (in all cases in any environment?), doesn’t work properly: the worm file is not attached to outgoing messages, and the message text appears different from what the worm intends.

To spread from an affected computer, the worm uses MS Outlook, obtains addresses from the MS Outlook Address Book as well as from the Windows Address Book, and sends messages there. The worm also sends an infected message to vb.master@angelfire.com each time the spreading routine is run.

The message Subject and Body should appear as follows (these do not because of a bug in worm code). The [%CurrentDate%] here is the current date.

Subject:
Message text:

Hey, now we can talk with this.. 🙂
Hello
I wrote a new messenger, so that we can talk with it.
Install the self extractable zip attached

My movie clips..
Hiii
I got a webcam, and I captured few movie clips of me.
Extract the
attached self extractable, to see them.

A lil naughty stuff..
Hey..
I got few great, erotic movie clips included in the self extractable

I downloaded these MP3s yesterday..
Howdy..
Hey, they r really great.. Extract the selfextractable zip to see them..

Just a little naughty stuff from me..
Hehehe..
See the cake I prepared for you.. bye 4 now buddy..

Virus Warning..
Hey, take care..
Forward this mail to everyone you know. Today, [%CurrentDate%] FBI
announced that a serious virus is spreading. It is a file with a .VBS
extension, much like Love Bug. See the zip for it

A Business Issue..
Sir,
My company is interested in the opportunities of creating a new
partnership with you. The presentation is attached, kindly see it and reply soon.

Legal Notice..
Sir/Madam
We are forced by our client to forward a legal notice to you dated
[%CurrentDate%]. Kindly see the attached details, and reply as soon as possible

Greeting Card 4 You..
Greeeeetings..
Hope you are doing fine. See the ECard attached 4 you..

When the worm’s EXE file is being run from the attachment, it copies itself to the Windows and Windows system directories with SysTray.exe and SysCheck.exe as names, and registers these files in the Windows registry auto-run section:

HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun
SystemTray = %WindowsDir%SysTray.exe

HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun
SystemCheck = %SystemDir%SysCheck.exe

note: the original SYSTRAY.EXE is located in the Windows system directory, not in the Windows directory as the worm does.

To hide its activity, the worm displays the following message:

Microsoft Windows
The application %ApplicationName% caused a general protection fault in
module Kernel.exe, and it will be terminated. Press OK to continue
[ OK ]

where %ApplicationName% is the worm’s file name.

On the 4th of any month, upon being executed before 5 a.m., the worm overwrites the C:AUTOEXEC.BAT file with a Trojan that erases all files in the “C:My Documents” and *.DLL files in the C:Windows directories. The Trojan code also displays the following messages:

Please wait while setup update files. This may take a few minutes..
Now loading Windows..

The worm also have backdoor component that “opens” affected computer for a remote hacker. The backdoor routine allows:

report drives in system, directories and files on drives
read,write,copy,delete a file
change, create, remove a directory
read,write registry keys
send email to a specified address
execute a file
forse Windows to exit

The worm code contains the text “3DStars server”, thus giving the worm name its name.