Backdoor.Beasty.B - Removal

These instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

1. Reverse the changes that the Trojan made to the registry, and then restart the computer.
2. Update the virus definitions.
3. Run a full system scan and delete all the files detected as Backdoor.Beasty.B.

For specific details on each of these procedures, read the following instructions.

1. Reversing the changes that the Trojan made to the registry

Because the Trojan modified the registry so that the Trojan runs when you run any .exe file, first make a copy of the Registry Editor as a file with the .com extension, and then run the copy. Then, edit the registry.

1. Do one of the following, depending on which version of Windows you are running:
   1. Windows 95/98 users:
      1. Click Start.
      2. Point to Programs.
      3. Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed to step 2, "Updating the virus definitions," of this section.
   2. Windows Me users:
      1. Click Start.
      2. Point to Programs.
      3. Point to Accessories.
      4. Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed to step 2, "Updating the virus definitions," of this section.
   3. Windows NT/2000 users:
      1. Click Start, and then click Run.
      2. Type command, and then press Enter. (A DOS window opens.)
      3. Type cd \winnt, and then press Enter.
      4. Go to step 2 of this section.
   4. Windows XP users:
      1. Click Start, and then click Run.
      2. Type command, and then press Enter. (A DOS window opens.)
      3. Type the following:
         
         cd\
         cd \windows
         
         Press Enter after typing each one.
         
      4. Proceed to step 2 of this section.
         
2. Type copy regedit.exe regedit.com, and then press Enter.
   
3. Type start regedit.com, and then press Enter. (The Registry Editor will open in front of the DOS window.)
   
   After you finish editing the registry, exit the Registry Editor, and then exit the DOS window as well.
   
4. Before continuing, Symantec strongly recommends that you back up the registry before you make any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified keys only. For instructions, read the document, "How to make a backup of the Windows registry."
   
5. Navigate to and select the key:
   
   HKEY_CLASS_ROOT\exefile\shell\open\command
   
   NOTE: The HKEY_CLASS_ROOT key contains many subkey entries that refer to other file extensions. One of these file extensions is .exe. Changing this extension can prevent any files ending with an .exe extension from running. Make sure that you completely browse throughout this path until you reach the \command subkey.
   
   Modify the HKEY_CLASS_ROOT\exefile\shell\open\command subkey, shown in the following figure:
   
   <<=== NOTE: Modify this key.
   
6. In the right pane, double-click the (Default) value.
7. Delete the current value data, and then type: "%1" %* (That is, type the characters: quote-percent-one-quote-space-percent-asterisk).
   
   NOTES
   • Under Windows 95/98/Me/NT, the Registry Editor automatically encloses the value within quotation marks. When you click OK, the (Default) value should look exactly like this:
     
     ""%1" %*"  
     
   • Under Windows 2000/XP, the additional quotation marks will not appear. When you click OK, the (Default) value should look exactly like this:
     
     "%1" %*
     
   • Make sure that you completely delete all the value data in the command key before typing the correct data. If you leave a space at the beginning of the entry, any attempt to run the program files will result in the error message, "Windows cannot find .exe." If this occurs, restart the entire process from the beginning of this document and make sure that you completely remove the current value data.
     
8. Navigate to and delete the key:
   
   HKEY_LOCAL_MACHINE\Software\Microsoft\Active Setup\Installed Components\{44AF0969-CC51-11CF-AAFA-06AA00F6115C}
   
9. Exit the Registry Editor.
10. Restart the computer.

2. Updating the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:

• Running LiveUpdate, which is the easiest way to obtain the virus definitions. These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate), in the "Protection" section, at the top of this writeup.
• Downloading the definitions using the Intelligent Updater. The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater), in the "Protection" section, at the top of this writeup.
  
  The Intelligent Updater virus definitions are available here. For detailed instructions on how to download and install the Intelligent Updater virus definitions from the Symantec Security Response Web site, click here.

3. Scanning for and deleting the infected files

1. Start your Symantec antivirus program and make sure that it is configured to scan all the files.
   • For Norton AntiVirus consumer products: Read the document, "How to configure Norton AntiVirus to scan all files."
   • For Symantec AntiVirus Enterprise products: Read the document, "How to verify that a Symantec Corporate antivirus product is set to scan All Files."
2. Run a full system scan.
3. If any files are detected as infected with Backdoor.Beasty.B, click Delete.

Technical Details