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Worm:Win32/Mydoom.B@mm
Detected by Microsoft Defender Antivirus
Aliases: W32/Mydoom.b@MM (McAfee) W32.Mydoom.B@mm (Symantec) WORM_MYDOOM.B (Trend Micro) Win32.Mydoom.B (CA)
Summary
Win32/Mydoom.B@mm is a mass-mailing worm that sends itself to e-mail addresses it finds on the infected computer. The worm also installs a .dll file that acts as a backdoor. After February 1, 2004, the worm attempts a denial-of-service (DoS) attack against www.sco.com.
To manually recover from infection by Win32/Mydoom.B@mm, perform the following steps:
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Disconnect from the Internet.
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End the worm process.
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Delete the worm files from your computer.
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Delete the worm registry entry.
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Take steps to prevent re-infection.
Disconnect from the Internet
To ensure that your computer is not actively infecting other computers, you should disconnect it from the Internet before proceeding.
End the worm process
Next you should end the worm process. This will stop your computer from infecting other computers.
To end the worm process
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Right-click the Taskbar and click Task Manager.
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Click the Processes tab.
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On the Processes tab, click Image Name to sort the running processes by name.
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Select the process taskmon.exe, and then click End Process.
Delete the worm files from your computer
Once you have stopped the worm from running, you should delete the actual worm code off your computer.
To delete the worm files from the hard disk
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Click Start, and then click Run.
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In the Open field, type %windir%
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Press Enter.
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Click the Name column to sort files by name.
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If the file taskmon.exe is found, delete it.
This will remove the malicious worm code from your computer.
If deleting files fails, use the following steps to verify that taskmon.exe is not running:
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Press Ctrl+Alt+Del once.
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Click Task Manager.
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Click the Processes tab.
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Confirm that taskmon.exe is not in the list.
Delete the worm registry entry
To delete the worm registry entry
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On the Start menu, click Run.
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Type regedit and click OK.
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Navigate to the key in the left pane: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
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In the right pane, right-click the value:
TaskMon <system folder>\taskmon.exe
or
TaskMon %Temp%\taskmon.exe -
Select Delete.
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Click Yes to delete the value.
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Repeat step 3 to step 6 for the registry key: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
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Close the Registry Editor.
Take steps to prevent re-infection
You should not reconnect your computer to the Internet until the computer is protected from re-infection.
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