Threat Explorer

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VBS.Masscal.Worm

VBS.Masscal.Worm

Discovered:
02 September 2003
Updated:
13 February 2007

VBS.Masscal.Worm is a file-infecting worm that drops a Trojan horse.

The worm is written in Microsoft Visual Basic Script.

Antivirus Protection Dates

  • Initial Rapid Release version 03 September 2003
  • Latest Rapid Release version 28 September 2010 revision 054
  • Initial Daily Certified version 03 September 2003
  • Latest Daily Certified version 28 September 2010 revision 036
  • Initial Weekly Certified release date 04 September 2003
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

When VBS.Masscal.Worm is executed, it performs the following actions:
  1. Copies itself to the following locations:
    • C:\Documents and Settings\All Users\Start Menu\Programs\Startup
    • C:\Documents and Settings\All Users\Start Menu\Programs
    • C:\Documents and Settings\All Users\Start Menu\Programs
    • C:\Documents and Settings\All Users\Desktop
    • C:\Documents and Settings\All Users\Documents
    • C:
    • %Temp%

      with the file names:
    • %User%'s_data_from_the_web.html.vbs
    • I_miss_you.txt.vbs
    • Tempfolder
    • Defragmenter.exe.vbs
    • ScanDisk32.exe.vbs
    • Win.Security.exe.vbs
    • www.symantec.html.vbs
    • Update.exe.vbs
    • Svchost.exe.vbs
    • Scan32.exe.vbs
    • Restore.exe.vbs
    • Spoolsv.exe.vbs


      Note: %Temp% is the default temporary folder, and %User% is the name of the default Windows user.


  2. Creates a VBS script, C:\Fire.kaz, that searches for .html, .htm, and .htt files in the following folders:
    • C:\Documents and Settings\All Users\Desktop
    • C:\Program Files
    • C:\Windows

      and prepends any files discovered with the following text:

      "<!-You are a victim of massacres.....->"

  3. Searches for files with .vbs and .vbe extensions in the following folders:
    • %Temp%
    • C:
    • C:\Windows
    • C:\Program Files
    • C:\Documents and Settings\%User%
    • C:\Documents and Settings\%User%\Desktop
    • C:\Documents and Settings\%User%\Desktop\1
    • C:\Documents and Settings\%User%\Cookies
    • C:\Documents and Settings\%User%\NetHood
    • C:\Documents and Settings\%User%\My Documents
    • C:\Documents and Settings\%User%\Local Settings
    • C:\Documents and Settings\%User%\Application Data
    • C:\Documents and Settings\%User%\Local Settings\Temp
    • C:\Documents and Settings\%User%\My Documents\My Received Files

  4. Infects any .vbs or .vbe files discovered by:
    1. Prefixing the file names with "MASS-"
    2. Prepending the file with the following text, followed by a copy of itself:

      "'You are a victim of massacres....."

  5. Prepends the following text to .txt, .rtf, and .ini files:

    "'You are a victim of massacres....."
    "Hello " & user & "."
    "'This is just to let you know, what could happen to your files, if you trust bill gates."
    "'I could've eliminated what I want, you know, but I am not as dirty as bill gates..."
    "'The name of this file was--->" & %filename% & " size: " & %filesize% & "-bytes, hehehe;) -Located on " & %parent_folder%
    "-This file was last Accessed in " & %DateLastAccessed% "-and created in " & %DateCreated%
    "-Have a nice day ;)"
    "|--=--=====-YOUR-FILE-BELOW-=====--=--|"

  6. Infects .html, .htm, and .htt files with extensions by:
    1. Prefixing the file name with "MASS-"
    2. Prepending the following text, following by a copy of C:\Fire.kaz in the form of VBScript:

      "<!-You are a victim of massacres.....->"

  7. Does one of the following:
    • Displays the message:

      "-I massacri-"
      "Sono il cervello, siamo la mente, siamo uniti !"

      and executes the executable routine explained in the step nine.
    • Displays the message:

      %script_name%
      "Error# " & %random_number% & %msg%


      Notes:
      - %script_name% is the name of the viral script file.
      - %random_number% is a random number generated by the worm.
      - %msg% is one of the following text strings:
      " - cannot find adecuated decoder."
      " - unable to find help context menu."
      " - missing file."
      " - device did not loaded properly."
      " " & %script_name% & " - is not a valid file."



  8. Drops a Trojan horse, %Windir%\SystemCal.exe, and runs it in background.


    Notes:
    - The Trojan horse can cause the windows display to not function properly.
    - %Windir% is a variable. The worm locates the Windows installation folder (by default, this is C:\Windows or C:\Winnt) and copies itself to that location.


  9. Creates the file, C:\Fire.bat, which sends all computers on the local network the following message:

    "I got massacred...:'()"



The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.
  1. Disable System Restore (Windows Me/XP).
  2. Update the virus definitions.
  3. Run a full system scan and repair all the files detected as VBS.Masscal.Worm.

For specific details on each of these steps, read the following instructions.

1. Disabling System Restore (Windows Me/XP)
If you are running Windows Me or Windows XP, we recommend that you temporarily turn off System Restore. Windows Me/XP uses this feature, which is enabled by default, to restore the files on your computer in case they become damaged. If a virus, worm, or Trojan infects a computer, System Restore may back up the virus, worm, or Trojan on the computer.

Windows prevents outside programs, including antivirus programs, from modifying System Restore. Therefore, antivirus programs or tools cannot remove threats in the System Restore folder. As a result, System Restore has the potential of restoring an infected file on your computer, even after you have cleaned the infected files from all the other locations.

Also, a virus scan may detect a threat in the System Restore folder even though you have removed the threat.

For instructions on how to turn off System Restore, read your Windows documentation, or one of the following articles:
For additional information, and an alternative to disabling Windows Me System Restore, see the Microsoft Knowledge Base article, "Antivirus Tools Cannot Clean Infected Files in the _Restore Folder," Article ID: Q263455.

2. Updating the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:

  • Running LiveUpdate, which is the easiest way to obtain virus definitions: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
  • Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater).

    The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.

3. Scanning for and repairing the infected files
  1. Start your Symantec antivirus software and make sure that it is configured to scan all the files.
  2. Run a full system scan.
  3. If any files are detected as infected with VBS.Masscal.Worm, click Repair.


Writeup By: Tony Lee