Discovered: October 8, 2004
Updated: February 13, 2007 12:28:13 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.
- Disable System Restore (Windows Me/XP).
- Update the virus definitions.
- Restart the computer in Safe mode or VGA mode.
- Run a full system scan and delete all the files detected as Backdoor.Berbew.K.
- Restore the Internet Security settings.
- Delete the value that was added to the registry.
For specific 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:
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.
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:
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 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 Backdoor.Berbew.K click Delete.
Note: If your Symantec antivirus product reports that it cannot delete an infected file, Windows may be using the file. To fix this, run the scan in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode." After you have restarted the computer in Safe mode, run the scan again.
After the files are deleted, you may leave the computer in Safe mode and proceed with section 4. When you have finished section 4, restart the computer in Normal mode.
5. To restore the Internet Security settings:
- Start Internet Explorer.
- On the Tools menu, click Internet Options.
- On the Security tab, set the desired level for every zone.
The easiest way to do this is to click Default Level for each one.
6. To delete the value from the registry
Important: 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.
- On the Windows taskbar, click Start > Run.
- Type the following:
regedit
- Click OK.
- Navigate to the following key:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\
ShellServiceObjectDelayLoad
- In the right pane, delete the following value:
"Web Event Logger" = "{79FEACFF-FFCE-815E-A900-316290B5B738}"
- Navigate to the following key:
HKEY_CLASSES_ROOT\CLSID\{79FEACFF-FFCE-815E-A900-316290B5B738}\
InProcServer32
- In the right pane, delete the following value:
"Default" = "[8 random characters.dll]"
- Navigate to the following key:
HKEY_CLASSES_ROOT\CLSID\{79FEACFF-FFCE-815E-A900-316290B5B738}\
InProcServer32
- In the right pane, delete the following value:
"Threading Model" = "Apartment"
- Navigate to the following key:
HKEY_CURRENT_USER\Software\Microsoft\Windows
- In the right pane, delete the following value:
"KKQHOOK" = "0x14"
- Reset the following values to their correct settings:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0\1601
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1\1601
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2\1601
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3\1601
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4\1601
- Exit the Registry Editor.
Writeup By: Asuka Yamamoto