Discovered: April 13, 2004
Updated: February 13, 2007 12:21:21 PM
Type: Trojan Horse
Systems Affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP
The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.
- Restart the computer in Safe mode or VGA mode.
- Reverse the changes made to the registry.
- Disable System Restore (Windows Me/XP).
- Update the virus definitions.
- Run a full system scan and delete all the files detected as Trojan.Mitglieder.I.
For details on each of these steps, read the following instructions.
1. 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.
2. To reverse the changes made to the registry
Because the worm modified the registry so that the worm runs when you run .exe files, first make a copy of the Registry Editor as a file with the .com extension, and then run the file.
- Do one of the following, depending on the version of Windows you are running:
- Windows 95/98 users:
- Click Start.
- Point to Programs.
- Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed with step B of this section.
- Windows Me users:
- Click Start.
- Point to Programs.
- Point to Accessories.
- Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed with step B of this section.
- Windows NT/2000 users:
- Click Start, and then click Run.
- Type command, and then press Enter. (A DOS window opens.)
- Type cd \winnt, and then press Enter.
- Go to step B of this section.
- Windows XP users:
- Click Start, and then click Run.
- Type command, and then press Enter. (A DOS window opens.)
- Type the following:
cd\
cd \windows
Press Enter after typing each one.
- Proceed with step B of this section.
- Type copy regedit.exe regedit.com
and then press Enter.
- Type start regedit.com
and then press Enter. (The Registry Editor opens in front of the DOS window.)
After you finish editing the registry, exit the Registry Editor, and then exit the DOS window as well.
- Before continuing, 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. For instructions, read the document, "How to make a backup of the Windows registry."
- Navigate to and select the key:
HKEY_LOCAL_MACHINE\Software\Classes\exefile\shell\open\command
Note: The HKEY_LOCAL_MACHINE\Software\Classes key contains many subkey entries that refer to other file extensions. One of these file extensions is .exe. Changing this extension can prevent any files ending with a .exe extension from running. Make sure that you completely browse through this path until you reach the \command subkey.
Modify the HKEY_LOCAL_MACHINE\Software\Classes\exefile\shell\open\command subkey, shown in the following figure:
<<=== NOTE: Modify this key.
- In the right pane, double-click the (Default) value.
- Delete the current value data, and then type:
"%1" %*
That is, type the characters: quote-percent-one-quote-space-percent-asterisk.
NOTES
- Under Windows 95/98/Me/NT, the Registry Editor automatically encloses the value within quotation marks. When you click OK, the (Default) value should look exactly like this:
""%1" %*"
- Under Windows 2000/XP, the additional quotation marks will not appear. When you click OK, the (Default) value should look exactly like this:
"%1" %*
- Make sure that you completely delete all the value data in the command key before typing the correct data. If you leave a space at the beginning of the entry, any attempt to run the program files will result in the error message, "Windows cannot find .exe." If this occurs, restart the entire process from the beginning of this document and make sure that you completely remove the current value data.
- Navigate to the key:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- In the right pane, delete the value:
"RealUpdater"="%System%\realupd.exe"
- Navigate to one of these keys:
- Windows 95/98/Me:
HKEY_USERS/.DEFAULT/Software/DateTime
- Windows NT/2000/XP:
HKEY_CURRENT_USER/Software/DateTime
- In the right pane, delete the values:
- "pid"="<Process ID>"
- "uid"="<Random 8 digit number>"
- "port"="<Listening Proxy Port>"
- Exit the Registry Editor.
- Restart the computer in Normal mode.
3. 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:
Note: 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.
4. 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.
5. To scan for and delete the infected files
- Start your Symantec antivirus program and make sure that it is configured to scan all the files.
- Run a full system scan.
- If any files are detected as infected with Trojan.Mitglieder.I, click Delete.
Writeup By: Scott Gettis