We're gradually updating threat actor names in our reports to align with the new weather-themed taxonomy. Learn about Microsoft threat actor names
Worm:Win32/Mimail.Q@mm
Detected by Microsoft Defender Antivirus
Aliases: WORM_MIMAIL.Q (Trend Micro) Win32/Mimail.Q!Worm (CA) W32/Mimail.q@MM (McAfee)
Summary
W32.Mimail.Q@mm is a mass-mailing worm that targets certain versions of Microsoft Windows. The worm sends itself as an attachment to e-mail addresses on the infected computer. The worm is activated when the user opens the attachment.
To manually recover from infection by Win32/Mimail.Q@mm, follow these steps:
- Disconnect from the Internet.
- Restart your computer in safe mode.
- End the worm process.
- Delete the worm file from your computer.
- Delete the worm registry entry.
- Scan with antivirus software.
- 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, 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 the computer in safe mode
- Remove all floppy disks and CDs from your computer, and then restart your computer.
- 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.
- From the Windows Advanced Options menu, select a safe mode option.
End the worm process
Ending the worm process will help stop your computer from infecting other computers as well as resolve the crashing, rebooting, and performance degradation issues caused by the worm.
To end the worm process
- 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 sys32.exe, and click End Process.
Delete the worm file from your computer
To delete the worm file from your computer
- Click Start, and click Run.
- In the Open field, type %windir%
- Click OK.
- Click Name to sort files by name.
- If sys32.exe is in the list, delete it.
- On the Desktop, right-click the Recycle Bin and click Empty Recycle Bin.
- Click Yes.
If deleting sys32.exe fails, follow these steps to verify that the file is 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 sys32.exe is not in the list.
Delete the worm registry entry
Win32/Mimail.Q@mm creates an entry in the Windows registry that attempts to run the worm every time your computer restarts. This entry should be deleted.
To delete the worm registry entry
- On the Start menu, click Run.
- Type regedit and click OK.
- In the left pane, navigate to the key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run - In the right pane, right-click the following value, if it exists:
system = %windir%\sys32.exe - Click Delete and click Yes to delete the value.
- Close the Registry Editor.
Scan with antivirus software
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.