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Discovered: July 07, 2004
Updated: February 13, 2007 12:25:10 PM
Type: Worm
Systems Affected: Windows

W32.Lovgate.AB@mm is mass-mailing worm that also spreads through open network shares. Once a system is infected, a remote attacker can access it. The email will have a variable subject and a file attachment with a .exe, .pif, .scr, .com, .rar, or .zip file extension.The worm also infects other Windows executable (.exe) files

W32.Lovgate.AB@mm spreads through the DCOM RPC vulnerability (described in Microsoft Security Bulletin MS03-026 ) using TCP port 135.

Antivirus Protection Dates

  • Initial Rapid Release version July 08, 2004
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version July 08, 2004
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date July 14, 2004

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

Technical Description

When W32.Lovgate.AB@mm runs, it performs the following actions:

  1. Copies itself as the following files:
    • %Windir%\SYSTRA.EXE
    • %Windir%\DRWTSN16.EXE
    • %System%\hxdef.exe
    • %System%\a(57 bytes)
    • %System%\IEXPLORE.EXE
    • %System%\RAVMOND.exe
    • %System%\internet.exe
    • %System%\svch0st.exe
    • %System%\kernel66.dll (With attributes set to Read Only, Hidden, and System).

      • %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.
      • %System% is a variable: The worm locates the System folder and copies itself to that location. By default, this is C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).

  2. Creates the following files:
    • %System%\ODBC16.dll (53,248 bytes)
    • %System%\msjdbc11.dll (53,248 bytes)
    • %System%\MSSIGN30.DLL (53,248 bytes)
    • %System%\WIN32VXD.DLL (53,248 bytes)

      which are identical backdoor components of the worm.

  3. Creates and executes the file, %System%\NetMeeting.exe (61,440 bytes). This is detected as W32.Lovgate.R@mm.

    When the file runs, it performs the following:
    1. Copies itself as %System%\spollsv.exe.

    2. Adds the value:

      "Shell Extension" = "%system%\spollsv.exe"

      to the registry key:


      so that the worm runs when you start Windows.

    3. Attempts to create %System%\a in other systems using the Microsoft Windows DCOM RPC Interface Buffer Overrun Vulnerability. This file is an FTP script that is used to get hxdef.exe from an infected system.

    4. May create these files in the %System% folder.
      • results.txt
      • win2k.txt
      • winxp.txt

        These files are not viral by themselves, and as such, are not detected.

  4. Creates the file, Autorun.inf, in the root folder of all the drives, except for CD-ROM drives, and then copies itself as Command.exe into those folders.

  5. Adds the values:

    "NetworkAssociates Inc" = "internet.exe"
    "Hardware Profile" = "%system%\hxdef.exe"
    "Program In Windows" = "%system%\IEXPLORE.EXE"
    "VFW Encoder/Decoder Settings" = "RUNDLL32.EXEMSSIGN30.DLL ondll_reg"
    "Protected Storage" = "RUNDLL32.EXE MSSIGN30.DLLondll_reg"
    "S0undMan" = "%system%\svch0st.exe"
    "Microsoft NetMeeting Associates, Inc." = NetMeeting.exe"

    to the registry key:


    so that the worm runs when you start Windows.

  6. Adds the values:

    "COM+ Event System"="DRWTSN16.EXE"

    to the registry key:


    so that the worm runs as a service when you start Windows 95/98/Me.

  7. On Windows NT/2000/XP, adds the value:


    to the registry key:

    HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows

  8. Creates the service, "Windows Management Protocol v.0 (experimental)," which is mapped to "Rundll32.exe msjdbc11.dll ondll_server."

  9. Creates the service, "_reg," which is mapped to "Rundll32.exe msjdbc11.dll ondll_server."

  10. Terminates all the processes that contains any of the following strings:
    • Duba
    • NAV
    • kill
    • RavMon.exe
    • Rfw.exe
    • Gate
    • McAfee
    • Symantec
    • SkyNet
    • rising

  11. Copies itself to all the network-shared folders and subfolders as any of the following:
    • WinRAR.exe
    • Internet Explorer.bat
    • Documents and Settings.txt.exe
    • Microsoft Office.exe
    • Windows Media Player.zip.exe
    • Support Tools.exe
    • WindowsUpdate.pif
    • Cain.pif
    • MSDN.ZIP.pif
    • autoexec.bat
    • findpass.exe
    • client.exe
    • i386.exe
    • winhlp32.exe
    • xcopy.exe
    • mmc.exe

  12. Creates a .zip file in the root folder of all the drives, unless the drive letter is A or B.

    File name: (One of the following)


    Extension: (One of the following)


  13. Scans all the computers on the local network, using the following passwords to attempt to log on as "Guest," "Admin," or "Administrator."


  14. If the worm successfully logs on to the remote computer, it will attempt to copy itself as:

    \\<remote computer name>\admin$\system32\NetManager.exe

    and to start the file as the service, "Windows Management NetWork Service Extensions."

    The worm also creates a network share, named "Media."

  15. Replies to all the incoming email messages when they arrive in the mailbox of certain MAPI-compliant email clients, such as Microsoft Outlook.

    If the original email is:

    Subject: <subject>
    From: <someone>@<somewhere.com>
    Message: <original message body>

    the worm will attempt to send the following email:

    Subject: Re: <subject>
    To: <someone>@<somewhere.com>
    '<someone>' wrote:
    > <original message body>

    <sender's domain> account auto-reply:

    followed by one of the following:

    If you can keep your head when all about you
    Are losing theirs and blaming it on you;
    If you can trust yourself when all men doubt you,
    But make allowance for their doubting too;
    If you can wait and not be tired by waiting,
    Or, being lied about,don't deal in lies,
    Or, being hated, don't give way to hating,
    And yet don't look too good, nor talk too wise;
    ... ... more look to the attachment.

    > Get your FREE <sender's domain>now! <

    Attachment: (One of the following)

    the hardcore game-.pif
    Sex in Office.rm.scr
    Deutsch BloodPatch!.exe
    How to Crack all gamez.exe
    Macromedia Flash.scr
    dreamweaver MX (crack).exe
    StarWars2 - CloneAttack.rm.scr
    Industry Giant II.exe
    DSL Modem Uncapper.rar.exe
    Britney spears nude.exe.txt.exe
    I am For u.doc.exe

  16. Retrieves the email addresses from an infected computer and sends an email with the following properties:

    Subject: (One of the following)

    Mail Delivery System
    Mail Transaction Failed
    Server Report

    Message: (One of the following)

    It's the long-awaited film version of the Broadway hit. The  message  sent as  a binary attachment.
    The message contains Unicode characters and has been sent as a binary attachment.
    Mail  failed.  For further assistance, please contact!

    Extension: (One of the following)


  17. Opens a backdoor on a random port.


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.


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. Restart the computer in Safe mode or VGA mode.
  4. Reverse the changes made to the registry.
  5. Run a full system scan and repair the files detected as W32.Lovgate.AB@mm.
For details on each of these steps, read the following instructions.

1. To disable 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:

When you are completely finished with the removal procedure and are satisfied that the threat has been removed, re-enable System Restore by following the instructions in the aforementioned documents.

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. To update 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. To restart the computer in Safe mode or VGA mode
Shut down the computer and turn off the power. Wait for at least 30 seconds, and then restart the computer in Safe mode or VGA mode.
  • For Windows 95, 98, Me, 2000, or XP users, restart the computer in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode."
  • For Windows NT 4 users, restart the computer in VGA mode.

4. To reverse the changes made to the registry

Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified keys only. Read the document, "How to make a backup of the Windows registry," for instructions.

  1. Click Start > Run.
  2. Type regedit

    Then click OK.

  3. Navigate to the key:


  4. In the right pane, delete the values:

    "WinHelp" = "%system%\realsched.exe"
    "Hardware Profile" = "%system%\hxdef.exe"
    "Program In Windows" = "%system%\IEXPLORE.EXE"
    "Microsoft NetMeeting Associates, Inc." = "NetMeeting.exe"
    "VFW Encoder/Decoder Settings" = "RUNDLL32.EXE MSSIGN30.DLL ondll_reg"
    "Protected Storage" = "RUNDLL32.EXE MSSIGN30.DLL ondll_reg"
    "Shell Extension" = "%system%\spollsv.exe"
    "S0undMan" = "%system%\svch0st.exe"

  5. Do one of the following:
    • Windows 95/98/Me: Go on to step f.
    • Windows NT/2000/XP: Skip to step h.

  6. Navigate to the key:


  7. In the right pane, delete the values:

    "SystemTra" = "%Windir%\SysTra.EXE"
    "COM+ Event System"="DRWTSN16.EXE"

    After you have deleted these values, skip to step j.

  8. Navigate to the key:

    HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows

  9. In the right pane, delete the value:


  10. Navigate to the key:


  11. In the left-hand pane, delete the subkey:


  12. Navigate to the key:


  13. In the left-hand pane, delete the key

    Windows Management Protocol v.0(experimental)

  14. Exit the Registry Editor.

5. To scan for and repair (or delete) the infected files
  1. Start your Symantec antivirus program 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 W32.Lovgate.AB@mm, click Repair. If the repair fails, the file must be one of the dropped files. Delete the file.
  4. Restart the computer in Normal mode. For instructions, read the section on returning to Normal mode in the document, "How to start the computer in Safe Mode."

Writeup By: Paul Mangan