Printer Friendly Page

Discovered: November 21, 2001
Updated: February 13, 2007 11:37:47 AM
Type: Trojan Horse

W32.Elem.Trojan is a Trojan horse that arrives appearing to be a key generator for Windows XP. It may also be available from a file sharing application service named Kazaa.

Antivirus Protection Dates

  • Initial Rapid Release version November 24, 2001
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version November 24, 2001
  • Latest Daily Certified version September 28, 2010 revision 036

Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Writeup By: Patrick Nolan

Discovered: November 21, 2001
Updated: February 13, 2007 11:37:47 AM
Type: Trojan Horse

This Trojan is actually a Pklite package containing zero-byte files. Its purpose is to overwrite existing files with the zero-byte files.

If the Trojan is executed, it does the following:

NOTE : The Trojan assumes that the system contains the path C:\Windows, and other default paths for systems running Windows 9x.

It creates the following zero-byte files:

  • C:\Autoexec.bat
  • C:\Config.sys
  • C:\Command.com
  • C:\Windows\Progman.ini
  • C:\Windows\Protocol.ini
  • C:\Windows\Win.ini
  • C:\Windows\Win.exe
  • C:\Windows\System.Ini
  • C:\Windows\System\Kernel32.dll
  • C:\Windows\System\Shell32.dll
  • C:\Windows\System\Winsock.dll

It may also create the files:
  • C:\Boot.exe (12,288 bytes)
  • C\Windows\Element.txt (594 bytes)
  • C:\Windows\Element.ico (766 bytes)

It may also create these shortcut files, which point to these files:
  • C:\Windows\Desktop\Element3.Lnk
  • C:\Windows\Start Menu\Element3.Lnk
  • C:\Windows\Start Menu\Programs\Startup\Element.Lnk
  • C:\Windows\Start Menu\Programs\Startup\Boot.Lnk

The file C:\Boot.exe is a program which will reboot the system if it is executed.
The file C:\Windows\Element.txt is a short text file which proclaims the Trojan to be the "ELEMENT" virus:

y()U h@vE jUsT bE|nG |nFEcTEd w|Th ThE "ELEMENT" V|RUS

This file contains other text that is related to the author.


Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

  • Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
  • Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
  • Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
  • Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
  • Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
  • Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
  • If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
  • Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
  • Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
  • Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
  • Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
  • If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
  • For further information on the terms used in this document, please refer to the Security Response glossary.

Writeup By: Patrick Nolan

Discovered: November 21, 2001
Updated: February 13, 2007 11:37:47 AM
Type: Trojan Horse

To remove this Trojan horse:

  1. Run LiveUpdate to make sure that you have the most recent virus definitions.
  2. Start Norton AntiVirus (NAV), and make sure that NAV is configured to scan all files. For instructions on how to do this, read the document How to configure Norton AntiVirus to scan all files.
  3. Run a full system scan.
  4. Delete all files that are detected as W32.Elem.Trojan. Deleted files must be either replaced from a clean backup or reinstalled.

Writeup By: Patrick Nolan