DonaldD.Trojan.C

SUMMARY

This Trojan allows a hacker to have remote access to the computer. It modifies the registry so that it runs when you start Windows.

Protection

• Virus Definitions (Intelligent Updater) September 12, 2001

Threat Assessment

Wild

• Wild Level: Low
• Number of Infections: 0 - 49
• Number of Sites: 0 - 2
• Geographical Distribution: Low
• Threat Containment: Easy
• Removal: Easy

Damage

• Damage Level: Low

Distribution

• Distribution Level: Low

TECHNICAL DETAILS

If the Trojan is run, it creates the following files:

• WindowsSystemRgl5max.exe
• WindowsSystemPon2dil.vxd

These files are loaded as a service when you start Windows. This is accomplished by making the following changes to the registry:

The Trojan creates the key

HKEY_LOCAL_MACHINESystemCurrentControlSetServicesVxDPON2DIL

with the values

StaticVxD  pon2dil.vxd
Start      00

and the key

HKEY_LOCAL_MACHINESystemCurrentControlSetServicesVxDPEN2D

with the value

dxt        <long string of byte sequences>


It also adds the value

@          <long string of random characters>

to the keys

HKEY_LOCAL_MACHINESystemCurrentControlSetControlKeyboard Layouts000080A

HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionTime ZonesW. Europe

Recommendations

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 (for example, all Windows-based computers should have the current Service Pack installed.). Additionally, please apply any security updates that are mentioned in this writeup, in trusted Security Bulletins, or on vendor Web sites.
• 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.

REMOVAL

To remove this Trojan, delete all files that are detected as DonaldD.Trojan.C and remove the two VxD subkeys that it added.

To remove the Trojan:

1. Run LiveUpdate to make sure that you have the most recent virus definitions.
2. Start Norton AntiVirus (NAV), and run a full system scan. Be sure that NAV is configured to scan all files.
3. Delete all files that are detected as DonaldD.Trojan.C.

To edit the registry:

CAUTION: We strongly recommend that you back up the system registry before you make any changes. Incorrect changes to the registry could result in permanent data loss or corrupted files. Please make sure that you modify only the keys that are specified. Please see the document How to back up the Windows registry before you proceed.

1. Click Start, and click Run. The Run dialog box appears.
2. Type regedit and then click OK. The Registry Editor opens.
3. Navigate to and select the following key:
   
   HKEY_LOCAL_MACHINESystemCurrentControlSetServicesVxDPON2DIL
   
   CAUTION: Make sure that you select PON2DIL subkey, and not any of its parent keys.
   
4. Press Delete, and then click Yes to confirm.
5. Navigate to and select the following key:
   
   HKEY_LOCAL_MACHINESystemCurrentControlSetServicesVxDPEN2D
   
   CAUTION: Make sure that you select the PEN2D subkey, and not any of its parent keys.
   
6. Press Delete, and then click Yes to confirm.
7. Exit the Registry Editor.