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Worm:Win32/Zotob.J
Detected by Microsoft Defender Antivirus
Aliases: No associated aliases
Summary
Worm:Win32/Zotob.J is a network worm that targets Microsoft Windows 2000 computers by exploiting the Windows Plug-and-Play buffer overflow vulnerability that is fixed with Microsoft Security Bulletin MS05-039. The worm can also infect computers running other Windows operating systems if it is delivered through e-mail, instant messaging, or other routes. The worm has a backdoor component that connects to an IRC server from the infected computer to receive commands from attackers.
To manually recover from infection by Worm:Win32/Zotob.J, follow these steps:
- Install security update MS05-039.
- 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 entries.
- Restart your computer.
- Take steps to prevent re-infection.
Install security update MS05-039
To install MS05-039 using Windows Update
- Go to the Windows Update Web site at windowsupdate.microsoft.com.
- On the Windows Update site, click Scan for Updates. Windows Update scans your computer and returns a list of critical updates, including service packs.
- In the Pick updates to install list, click Critical Updates and Service Packs. Windows Update creates a list of the updates appropriate for your computer, including MS05-039 if it is not installed. Critical updates are selected for download automatically.
- Click Review and install updates, and then click Install Now. You may need to restart your computer after installing the updates.
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
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 HPSV.exe, and click End Process.
Delete the worm file from your computer
To delete the worm files from your computer
- Click Start, and click Run.
- In the Open field, type the name of the system folder, for example, C:\Winnt\System32
- Click OK.
- Click Name to sort files by name.
- If HPSV.exe is in the list, delete it.
- On the Desktop, right-click the Recycle Bin and click Empty Recycle Bin.
- Click Yes.
If deleting the file fails, follow these steps to verify that process HPSV.exe 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 HPSV.exe is not in the list.
Delete the worm registry entries
Worm:Win32/Zotob.J creates entries in the Windows registry. These entries should be deleted.
To delete the worm registry entries
- 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: HPSV.exe
- Click Delete and click Yes to confirm the deletion.
- Repeat steps 3 through 5 for each of the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
HKEY_CURRENT_USER\SOFTWARE\Microsoft\OLE
HKEY_CURRENT_USER\SYSTEM\CurrentControlSet\Control\Lsa
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\OLE
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa - 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.