Trojan.Metajuan is a Browser Helper Object that hijack homepage and redirects Internet Explorer on unwanted websites. It can also download potentially malicious files on to the infected computer.Trojan.Metajuan may be dropped by other malware or downloaded from malicious Web sites using Internet Explorer exploits.When the Trojan is executed, it creates the following registry entry:
HKEY_CLASSES_ROOT\CLSID\68D5CF1D-EC5C-4bdd-A9EF-F0E517565D50}\InprocServer32\"Default" = "%Temp%\[NAME OF TROJAN EXECUTABLE].dll"
The Trojan may then download potentially malicious files on to the compromised computer.
- 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.
- 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.
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.
- 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.
- 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.
Since Trojan.Metajuan drops many files at system root folder, good files can be sometimes mistaken as infected files. Thus, manual spyware removal is recommended for experienced users only, such as IT specialists or highly qualified system administrators. For other users, we recommend malware and spyware removal applications.