F-Secure Virus Descriptions : Antimarc

NAME:

Antimarc

This virus infects Word97 documents and spreads via global electronic channels: chat-net mIRC and MS Outlook Express. This is the first known macro virus that uses mIRC and Outlook to spread infection. The virus contains the comments:

   W97M/antiMARC by Lord Natas [Codebreakers 98]
   with special thanks to Rhape79
   "We're just the toys in the hands of another"

The virus code contains 15 macros in one module "Antimarc": antiMARC, mIRCDropper, OE, Delay, AutoClose, AutoExec, AutoOpen, FileClose, FileExit, FileSave, FileSaveAs, ToolsMacro, FileTemplates, ViewVBCode, FormatStyle.

The antiMARC macro is the main virus macro. Other ones are either do-nothing ones (AutoExec), or call this macro to infect Word97 documents. The mIRCDropper macro sends the infected documents to chat-network, the OE macro sends the infected message by using Outlook Express.

The virus replicates in Word environment on activating of any auto-macro except AutoExec, i.e. the virus infects the global macro area and documents on documents opening, closing, saving, saving with new name, on entering the Tools/Macro, File/Templates and other menus. To copy its code the virus uses export/import functions via the SYSTEM\MICROSOF.386 file that is created in the Windows directory.

Depending on the system random counter the virus also executes its Chat and Outlook spreading routines. While sending its copy to the Chat the virus uses the MIRC32.EXE utility. It disables mIRC warning messages in the system mIRC C:\MIRC\MIRC.INI file, creates the infected file C:\WINDOWS\XXXPASSWORDS.DOC and the script C:\MIRC\SCRIPT.INI.

The virus script file contains the instructions that send the infected XXXPASSWORDS.DOC file to all users that join the Chat. If there is a message with "marcsux" substring, the virus sends to the host of this message the text: "#gotinfected777 X". The virus also sends the message to the Chat:

  marc FuCk YoU FaScIsT
  warblade STILL SUCKING MARC's COCK?? eh, sure you do!!
  super Hey M0therfux0r, shove X/W up yer fat pimple-covered ass!
  super 'We do not support the distribution of virii' - i guess
  you do now, bitch!
  #gotinfected777 Kick Me! - I'm InFeCtEd!

While sending itself by using MS Outlook Express the virus creates random named infected file on the C: drive, selects 20th address in Address Book, creates a new message, fills it with random letters, attaches the infected file and appends the footer line:

  J97Z/nagvZNEP ol Ybeq Angnf [Pbqroernxref 98]

This procedure is not language independent and does work only under German version of Outlook Express.

[Eugene Kaspersky]