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
Any program within this subclass can have additional Trojan functions. It should also be noted that many worms use more than one method in order to spread copies via networks.

Class: Virus

Viruses replicate on the resources of the local machine. Unlike worms, viruses do not use network services to propagate or penetrate other computers. A copy of a virus will reach remote computers only if the infected object is, for some reason unrelated to the virus function, activated on another computer. For example: when infecting accessible disks, a virus penetrates a file located on a network resource a virus copies itself to a removable storage device or infects a file on a removable device a user sends an email with an infected attachment.

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Platform: MSExcel

Microsoft Excel (MS Excel) is a popular spreadsheet program and part of the Microsoft Office productivity suite. Excel files have .xls or .xlsx extensions.


Technical Details

This is Excel97 macro virus. It hooks sheets activation event and infects corresponding files. It also creates the infected file ALEVIRUSCS.XLM in the Excel startup directory and disables the Macro Virus Protection by running a short macro in a temporary MS Word application that is executed by the virus in hidden window.

The virus uses procedure from the "Macro.Excel97.Papa" virus to send own copies via e-mail, but in contrast to Papa virus it also infects other workbooks. So, when just infected workbook will be opened next time, this workbook (that may contain confidential information) will be sent to addresses stored in Outlook address book.

The e-mail message has:

Fwd: Millions DEADS!!!
Urgent info inside. The III War is Begin!!! Read The Secret's in XLS!

To the message the infected workbook is attached.

After infection the virus creates the directories:

c:Arquivos de programasMicrosoft OfficeOfficeXLINICIO
c:Programs FilesMicrosoft OfficeOfficeXLINICIO

Latest closed document the virus saves in the "C:WINDOWS" folder with names WAR3.XLS, SEXO.XLS, FONE.XLS, AVP.XLS, CAIXA.XLS.

The virus also tries to replace default script of many popular IRC clients by own one which sends infected workbook to everybody joined to IRC channel.

On May 19th the virus shows office assistent balloon with message:

Primeiro Excel97>Email>MIRC> Virus Brasileiro by AlevirusSCS [Brasil]1999!
Em Breve Alevirus Excel97 Formula Virus!Mande-me Um EMAIL!

The virus blocks Visual Basic Editor hot-key displays message box:

Este programa executou uma instrucao ilegal por favor feche o Windows
e reinicie.

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