Threat Explorer

The Threat Explorer is a comprehensive resource consumers can turn to for daily, accurate, up-to-date information on the latest threats, risks and vulnerabilities.

DeepThroat.Trojan

DeepThroat.Trojan

Updated:
13 February 2007
Also Known As:
Backdoor.deepthroat.b

DeepThroat.Trojan has no visual indicators of infection. When executed, this Trojan horse modifies the system registry to enable itself to run as a service. When installed on a Microsoft Windows system, it lets others gain full access to the system through a network connection.



Norton Internet Security/Norton Internet Protection users
If you are using either of these Symantec firewall programs, the name that is used by the Trojan Block rule to prevent the Trojan from being downloaded to your computer is different from the name that is used by Norton AntiVirus to detect the same threat if it were actually run on your computer or received in email.

Norton Internet Security/Norton Internet Protection will block DeepThroat.Trojan from being downloaded to your computer using the Block Rule DeepThroat.

Antivirus Protection Dates

  • Initial Rapid Release version 15 May 2000
  • Latest Rapid Release version 15 January 2018 revision 020
  • Initial Daily Certified version 15 May 2000
  • Latest Daily Certified version 15 January 2018 revision 024
  • Initial Weekly Certified release date pending
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

This Trojan horse opens a large number of ports for listening. It can be used to allow unauthorized access to your computer.

The file name of the attachment might vary. When executed, the Trojan horse sets the path and file name of the attachment (usually c:\windows\temp\filename.exe) equal to the "SystemDLL32" value in following registry key:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run

Recommendations

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

  • Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
  • 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.
  • Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
  • Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
  • Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
  • Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
  • If a 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.
  • Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
  • Isolate compromised computers quickly to prevent threats from spreading further. 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.
  • If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
  • For further information on the terms used in this document, please refer to the Security Response glossary.

Scan your computer with Norton AntiVirus.
  1. Restart your computer in MS-DOS mode.
  2. Delete any files detected by Norton AntiVirus as DeepThroat.Trojan.
  3. Restart the system.
  4. Edit the Windows registry using Regedit.exe. Go to the following registry key:

    HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
  5. On the right side of the window, look for the registry entry with SystemDLL32 as its name field. Right-click SystemDLL32 and click Delete.
  6. Restart the machine again, look at the registry, and make sure that the Trojan horse did not reinstall itself.

Writeup By: Edric Ta