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Rosscoe
17-09-2003, 11:39 PM
Hi have managed to remove a trojan horse virus called Backdoor Beastdoor but now cannot get Internet explorer to function correctly, when you enter Symantec web address it goes to another site,the computer has also started to not respond.We are running Xp with Avg anti-virus and have had no previous problems.AVg say to check the internet connection? or Internet explorer but how?Please advise.

Babe Ruth
17-09-2003, 11:59 PM
From the Symantec site Symantec_Site (http://securityresponse.symantec.com/avcenter/venc/data/backdoor.beasty.e.html)
in case you can't get to it the full instructions are here:

When Backdoor.Beasty.E is executed, it does the following:

1. Copies itself as these files:
* %Windows%\Svchost.exe
* %System%\Wbem\Wb.com
* %System%\Com\Mscom32.com

2. Creates the registry key:

HKEY_LOCAL_MACHINE\Software\Microsoft\Active Setup\Installed Components\
{45DD0432-AA51-31EF-EEFA-06AA12E6115C}\StubPath = %System%\wbem\wb.com
3. Adds the value:

COM Service %System%\COM\mscom32.com

to the registry key:

HKEY_CURRENT_USER\Software\Microsoft\Windows\Curre ntVersion\
Policies\Explorer

so that the worm runs when you start Windows.
4. Ends the following processes:
* ... (long list of executables here)

5. May add the value, shell32.pif to the following registry keys:

HKEY_CLASSES_ROOT\comfile\shell\open\command
HKEY_CLASSES_ROOT\exefile\shell\open\command
HKEY_CLASSES_ROOT\piffile\shell\open\command

so that the Trojan is executed each time you execute a .com, .exe, or .pif file.

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

* Turn off and remove unneeded services. By default, many operating systems install auxiliary services that are not critical, such as an FTP server, telnet, and a Web server. These services are avenues of attack. If they are removed, blended threats have less avenues of attack and you have fewer services to maintain through patch updates.
* If a blended threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
* Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
* Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
* Configure your email server to block or remove email that contains file attachments that are commonly used to spread viruses, such as .vbs, .bat, .exe, .pif and .scr files.
* Isolate infected computers quickly to prevent further compromising your organization. Perform a forensic analysis and restore the computers using trusted media.
* Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.

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

NOTES:

* If the Trojan has not yet run—that is, the Trojan's file was copied to your computer but has not run—you should be able to follow the instructions in sections 1 and 2, which discuss detecting and removing this file. (If the Trojan has run, in most cases you will not be able to follow these instructions, as the modifications that the worm made will prevent you from doing so.)
* If the Trojan has run, or if you are not sure, first follow the instructions in section 3. After completing those instructions, follow the steps in sections 1 and 2.

1. Update the virus definitions.
2. Run a full system scan and delete all the files detected as Backdoor.Beasty.E.
3. Reverse the changes made to the registry.

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

1. 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 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).
* 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).

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.

2. 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.E, click Delete.


3. Reversing the changes made to the registry
If the Trojan has already executed, it may have modified the registry so that the Trojan is executed each time you execute a .com, .exe, or .pif file.
To avoid this, first make a copy of the Registry Editor as a file with the .scr extension, and then run that particular file.

1. Restart the computer in Safe mode. All the Windows 32-bit operating systems, except Windows NT, can be restarted in Safe mode. For instructions on how to do this, read the document, "How to start the computer in Safe Mode."
2. Do one of the following, depending on the version of Windows you are running:
* 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 c of this section.
* 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 c of this section.
* 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 c of this section.
* 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 c of this section.

3. Type copy regedit.exe regedit.scr

and then press Enter.
4. Type start regedit.scr

and then press Enter. (The Registry Editor opens in front of the DOS window.)

After you finish editing the registry, exit the Registry Editor, and then exit the DOS window as well.
5. Before continuing, Symantec strongly recommends that you back up the registry before making 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."
6. Navigate to and select the key:

HKEY_CLASSES_ROOT\exefile\shell\open\command

NOTE: The HKEY_LOCAL_MACHINE\Software\Classes 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 a .exe extension from running. Make sure that you completely browse through this path until you reach the \command subkey.

Modify the HKEY_CLASSES_ROOT\exefile\shell\open\command subkey

7. In the right pane, double-click the (Default) value.
8. 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 section, and make sure that you completely remove the current value data.

9. Navigate to the key:

HKEY_CLASSES_ROOT\comfile\shell\open\command
10. Repeat the procedure described in steps g and h.
11. Navigate to the key:

HKEY_CLASSES_ROOT\piffile\shell\open\command

Repeat the procedure described in steps g and h.
12. Navigate to the key:

HKEY_CURRENT_USER\Software\Microsoft\Windows\Curre ntVersion\
Policies\Explorer
13. In the right pane, delete the value:

COM Service %System%\COM\mscom32.com
14. Exit the Registry Editor.
15. Restart the computer and follow the instructions in sections 1 and 2.


Babe.