Parent class: VirWare
Viruses and worms are malicious programs that self-replicate on computers or via computer networks without the user being aware; each subsequent copy of such malicious programs is also able to self-replicate. Malicious programs which spread via networks or infect remote machines when commanded to do so by the “owner” (e.g. Backdoors) or programs that create multiple copies that are unable to self-replicate are not part of the Viruses and Worms subclass. The main characteristic used to determine whether or not a program is classified as a separate behaviour within the Viruses and Worms subclass is how the program propagates (i.e. how the malicious program spreads copies of itself via local or network resources.) Most known worms are spread as files sent as email attachments, via a link to a web or FTP resource, via a link sent in an ICQ or IRC message, via P2P file sharing networks etc. Some worms spread as network packets; these directly penetrate the computer memory, and the worm code is then activated. Worms use the following techniques to penetrate remote computers and launch copies of themselves: social engineering (for example, an email message suggesting the user opens an attached file), exploiting network configuration errors (such as copying to a fully accessible disk), and exploiting loopholes in operating system and application security. Viruses can be divided in accordance with the method used to infect a computer:- file viruses
- boot sector viruses
- macro viruses
- script viruses
Class: Email-Worm
Email-Worms spread via email. The worm sends a copy of itself as an attachment to an email message or a link to its file on a network resource (e.g. a URL to an infected file on a compromised website or a hacker-owned website). In the first case, the worm code activates when the infected attachment is opened (launched). In the second case, the code is activated when the link to the infected file is opened. In both case, the result is the same: the worm code is activated. Email-Worms use a range of methods to send infected emails. The most common are: using a direct connection to a SMTP server using the email directory built into the worm’s code using MS Outlook services using Windows MAPI functions. Email-Worms use a number of different sources to find email addresses to which infected emails will be sent: the address book in MS Outlook a WAB address database .txt files stored on the hard drive: the worm can identify which strings in text files are email addresses emails in the inbox (some Email-Worms even “reply” to emails found in the inbox) Many Email-Worms use more than one of the sources listed above. There are also other sources of email addresses, such as address books associated with web-based email services.Read more
Platform: VBS
Visual Basic Scripting Edition (VBScript) is a scripting language interpreted by Windows Script Host. VBScript is widely used to create scripts on Microsoft Windows operating systems.Description
Technical Details
This worm spreads in e-mail messages. The worm itself is a DOS EXE file about 30K in length. When run, it installs itself to the Windows directory with the TYPEDEF.EXE name and registers itself in a WIN.INI file in the auto-run section. To hide its activity, the worm then displays a fake message and exits:
PKSFX Self Extraction Utility Version 2.50 03-01-1999
Copr. 1989-1999 PKWARE Inc. All Rights Reserved. Shareware Version
PKZIP Reg. U.S. Pat. and Tm. Off. Patent No. 5,051,745
Error in SFX - Unable to extract !!
While installing, the worm tries four "hardcoded" variants of the Windows directory name: C:WINDOWS, C:WIN95, C:WIN98, C:WINNT, and fails to install itself when Windows is installed in the directory with different name.
Upo the next Windows start-up, the worm copy is activated as a TYPEDEF.EXE file from the Windows directory. The worm runs a counter that is stored in the TYPEDEF.INI file and is incremented on each TYPEDEF.EXE file start (i.e., on each Windows start-up). Depending on that counter (once per three runs), the worm creates a TYPEDEF.VBS file and writes a VisualBasicScript program to there that sends the worm copy attached to e-mail messages.
That program opens MS Outlook, reads e-mail addresses from the AddressBook and sends messages to all of them. The message subject is: "Check this out". The message text and attached file name are randomly selected from eight variants:
It seems internet explorer 5 has some kinda bug which leaves some secuirity holes and allows somebody to write files onto your system. I downloaded this fix. I am sending it as an attatchment.
Attach: IE5FIX.EXEI found something to help get rid of those irritating ads that pop up when you go to some sites. I am sending it as an attatchment.
Attach: NOADS.EXEHere are some images you might like. You really need to check them out.
Attach: IMAGES.EXEI am sending some of the coolest pictures known to man. You might want to check them out.
Attach: COOLPICS.EXEPlease take a look at these documents. I am sending them compressed in a self extractor.
Attach: DOCS.EXEI am sending you the setup of the latest shareware version of PKZip. It gives excellent compression ratios. You might want to install it.
Attach: PKSETUP.EXEI downloaded a patch to some bug in Internet Explorer. I am sending it as an attatchment.
Attach: PATCH.EXEI downloaded a screen saver with cool effects. I am sending you its installation. Do try it out
Attach: SCRNSAVE.EXE
Also depending on the counter, the worm displays the text:
------ --
- -- - --
-- ---- ---- ---- ---- --
-- -- -- -- -- -- -- -----
-- -- -- ---- ---- ------ -- --
-- -- -- -- -- -- -- --
---- ---- ---- ---- ----- --- --
----- --- --
-- -- -- --
--- --- -- --- --
--- -- -- -- -----
--- ----- -- ----- -- --
-- -- -- -- -- -- -- -- --
----- --- -- --- --- -- --- --
!!! and scrambled eggs !!!
I-WORM.TSSE
Coded by [Offset]
The worm also contains the text strings:
The Tossed Salad and Scrambled Eggs Worm = I-Worm.TSSE. Coded by [Offset]
Read more
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