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Backdoor:Win32/Berbew.AM
Detected by Microsoft Defender Antivirus
Aliases: BackDoor-AXJ.gen (McAfee) Backdoor.Berbew.F (Symantec)
Summary
Backdoor:Win32/Berbew.AM is a backdoor Trojan that targets computers running Microsoft Windows 2000 or Windows XP. The Trojan installs silently on the target computer. It can capture and send personal information from an infected computer to a Web site. It can also download files from Web sites and run them on the infected computer.
To manually recover from infection by Backdoor:Win32/Berbew.AM, perform the following steps:
- Disconnect from the Internet.
- End hidden Internet Explorer processes.
- Delete the Trojan files from your computer.
- Delete the Trojan registry entries.
- Restart your computer.
- Take steps to prevent re-infection.
Disconnect from the Internet
To help ensure that your computer is not actively infecting other computers, you should disconnect it from the Internet before proceeding. Print this Web page or save a copy on your computer; then unplug your network cable and disable your wireless connection. You can reconnect to the Internet after completing these steps.
End hidden Internet Explorer processes
Ending the hidden Internet Explorer processes will help stop your computer from infecting other computers as well as resolve the crashing, rebooting, and performance degradation issues caused by the Trojan.
To end Internet Explorer processes
- Press CTRL+ALT+DEL once and click Task Manager.
- Click Processes and click Image Name to sort the running processes by name.
- Select the process iexplore.exe, and click End Process.
- Repeat step 3 for all other instances of iexplore.exe in the list.
Delete the Trojan files from your computer
To delete the Trojan files from your computer
- Click Start, and click Run.
- In the Open field, type %windir%\system32
- Click OK.
- Click Name to sort files by name.
- Delete any of the following files that appear in the list: surf.dat, kk32.vxd, kk32.dll, dnkk.dll.
- On the Desktop, right-click the Recycle Bin and click Empty Recycle Bin.
- Click Yes.
If deleting files fails, follow these steps to verify that the files are not running:
- Press CTRL+ALT+DEL once and click Task Manager.
- Click Processes and click Image Name to sort the running processes by name.
- Confirm that the file names are not in the list.
Delete the Trojan registry entries
To delete the Trojan registry entries
- On the Start menu, click Run.
- Type regedit and click OK. The Registry Editor opens.
- In the left pane, navigate to the registry key: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\ShellServiceObjectDelayLoad
- In the right pane, right-click the following value, if it exists: Web Event Logger
- Click Delete and click Yes to delete the value.
- In the left pane, navigate to the key: HKEY_CLASSES_ROOT\CLSID\{79FEACFF-FFCE-815E-A900-316290B5B738}
- In the left pane right-click the registry key: {79FEACFF-FFCE-815E-A900-316290B5B738}
- Click Delete and click Yes to delete the key.
- Close the Registry Editor.
Restart your computer
To restart your computer
- On the Start menu, click Shut Down.
- Select Restart from the drop-down list and click OK.
Take steps to prevent re-infection
Do not reconnect your computer to the Internet until the computer is protected from re-infection. See the "Preventing Infection" section for more information.