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Backdoor:Win32/Berbew.AA
Detected by Microsoft Defender Antivirus
Aliases: Backdoor-AXJ.gen (McAfee) Backdoor.Berbew (Symantec) Troj/Webber-H (Sophos)
Summary
Backdoor:Win32/Berbew.AA is a backdoor Trojan that downloads to a computer using another downloader Trojan that is sent in e-mail. Backdoor:Win32/Berbew.AA retrieves locally cached passwords and sends them to a Web site. It also opens certain ports.
To manually recover from infection by Backdoor:Win32/Berbew.AA, perform the following steps:
- Disconnect from the Internet
- End hidden Internet Explorer processes
- Delete the Trojan files from the hard disk
- 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 the 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 iexplore.exe processes.
Delete the Trojan files from the hard disk
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 if they are in the list: dz32x.vxd or dz32x.dat
- On the Desktop, right-click the Recycle Bin and click Empty Recycle Bin.
- Click Yes to confirm that you want to empty the recycle bin.
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\{79FB9088-19CE-715E-D900-216290C5B738}
- In the left pane right-click the registry key: {79FB9088-19CE-715E-D900-216290C5B738}
- 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
You should not reconnect your computer to the Internet until the computer is protected from re-infection. See the "Preventing Infection" section for more information.