Skip to main content
Skip to main content
Microsoft Security Intelligence
Cart 0 items in shopping cart
Sign in
Published Oct 12, 2005 | Updated Sep 15, 2017

TrojanProxy:Win32/Mitglieder.AA

Detected by Microsoft Defender Antivirus

Aliases: W32/Bagle.o!proxy (McAfee) W32/Bagle.dll.gen (McAfee) WORM_BAGLE.P (Trend Micro) Trojan.Mitglieder (Symantec)

Summary

TrojanProxy:Win32/Mitglieder.AA is a backdoor Trojan that targets computers running certain versions of Microsoft Windows. The Trojan injects its code into the Windows Explorer process explorer.exe. The Trojan monitors a randomly chosen TCP port for commands from attackers. Attackers can use the computer as a Web and SMTP proxy. 
To manually recover from infection by TrojanProxy/Win32.Mitglieder.AA, perform the following steps:
  1. Disconnect from the Internet.
  2. Restart your computer in safe mode.
  3. End the Trojan process.
  4. Delete the Trojan file from your computer.
  5. Delete the Trojan registry entry.
  6. Restart your computer.
  7. Take steps to prevent re-infection.

Disconnect from the Internet

To help ensure that your computer is not actively infecting other computers, 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.

Restart your computer in safe mode

To start your computer in safe mode
  1. Remove all floppy disks and CDs from your computer, and then restart your computer.
  2. When prompted, press F8. If Windows starts without displaying the Please select the operating system to start menu, restart your computer. Press F8 after the firmware POST process completes, but before Windows displays graphical output.
  3. From the Windows Advanced Options menu, select a safe mode option.

End the Trojan process

To end the Trojan process
  1. Press CTRL+ALT+DEL once and click Task Manager.
  2. Click Processes and click Image Name to sort the running processes by name.
  3. Select the process syswrun4x.exe, and click End Process.

Delete the Trojan file from your computer

To delete the Trojan file from your computer
  1. Click Start, and click Run.
  2. In the Open field, type %windir%\system32
  3. Click OK.
  4. Click Name to sort files by name.
  5. If syswrun4x.exe is in the list, delete it.
  6. On the Desktop, right-click the Recycle Bin and click Empty Recycle Bin.
  7. Click Yes.
If deleting the file fails, use the following steps to verify that process syswrun4x.exe is not running:
  1. Press CTRL+ALT+DEL once and click Task Manager.
  2. Click Processes and click Image Name to sort the running processes by name.
  3. Confirm that syswrun4x.exe is not in the list.

Delete the Trojan registry entry

To delete the Trojan registry entry
  1. On the Start menu, click Run.
  2. Type regedit and click OK.
  3. In the left pane, navigate to the key:
    HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
  4. In the right pane, right-click the following value, if it exists: usrgtway.exe
  5. Click Delete and click Yes to confirm the deletion.
  6. Close the Registry Editor.

Restart the computer

To restart the computer
  1. On the Start menu, click Shut Down.
  2. Select Restart from the drop-down list and click OK.

Take steps to prevent re-infection

Do not reconnect the computer to the Internet until the computer is protected from re-infection. See the "Preventing Infection" section for more information.
Follow us