SymbOS.Romride.J

SUMMARY

SymbOS.Romride.J is a Trojan horse that runs on the Symbian OS, which is used as the operating system for Nokia Series 60 cellular telephones. The Trojan drops corrupt files onto the compromised device. It also installs a bootstrap component that always restarts the phone immediately, which causes the phone to keep on restarting.

Protection

• Virus Definitions (LiveUpdate™ Daily) November 10, 2006
• Virus Definitions (LiveUpdate™ Weekly) November 15, 2006
• Virus Definitions (Intelligent Updater) November 10, 2006
• Virus Definitions (LiveUpdate™ Plus) November 10, 2006

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
• Payload: Drops corrupt files onto the device, which may cause it to restart continuously

Distribution

• Distribution Level: Low

TECHNICAL DETAILS

The Trojan reportedly arrives as the following file:

Bluetooth.sis

When the user opens this file, the phone installer displays a dialog box to warn the users that the application may be coming from an untrusted source and may cause potential problems. If the user clicks yes, the device displays the following message prompting the user to install the threat:

Install
Bluetooth

When SymbOS.Romride.J is executed, it performs the following actions:

1. Drops the following corrupt files:
   
   
   • C:Helzim.exe, which is the executable component of the threat
   • C:SystemBootdataCommonData.D00
   • C:SystemBootdataFirstBoot.dat
   • C:SystemBootdataLocaleData.D01
   • C:SystemInstallinstall.log
   • C:SystemMail0001000
   • C:SystemMail0100000
   • C:SystemMail0100001
   • C:SystemSchedulesSchedules.dat
     
     Note: The files dropped to C:System folder are all text files.
     
     
2. Creates the following file:
   
   systeminstallBluetooth.sis
   
   Note: This file is actually created by the Installer, not the threat.

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

1. Install a file manager program on the device.
   
   
2. Enable the option to view the files in the system folder.
   
   
3. Delete the following files:
   
   
   • C:Helzim.exe, which is the executable component of the threat
   • C:SystemBootdataCommonData.D00
   • C:SystemBootdataFirstBoot.dat
   • C:SystemBootdataLocaleData.D01
   • C:SystemInstallinstall.log
   • C:SystemMail0001000
   • C:SystemMail0100000
   • C:SystemMail0100001
   • C:SystemSchedulesSchedules.dat
     
     
4. Exit the file manager.