Updated: February 13, 2007 11:55:42 AM
The Emperor virus carries a payload that displays the following message when triggered:
I will grind my hatred upon the loved ones.
Despair will be brought upon the hoping childs of happiness. Wherever there is joy the hordes of the eclipse will pollute sadness and hate under the reign of fear.
Antivirus Protection Dates
- Initial Rapid Release version December 21, 2000
- Latest Rapid Release version October 19, 2017 revision 034
- Initial Daily Certified version December 21, 2000
- Latest Daily Certified version October 20, 2017 revision 003
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.
While the above message is on the screen, the virus starts writing data to the hard drive beginning at the first sector (Master Boot Record). Data that is overwritten by the virus is not recoverable. After overwriting the hard drive, the virus alters code in the Flash BIOS. This is an attempt to kill the Flash BIOS in the same manner as the W95.CIH virus.
Once the MBR is infected, the virus must be running in order to access the hard drive. The same also applies to infected floppy disks. An infected floppy cannot be read from or written to by a clean system. The data on the hard drive and floppy are still intact. If the virus finds specific bytes present in the MBR during infection, it will zero out the CMOS RAM. If this happens, the current CMOS settings are lost.
If the payload has not been triggered, restoring the infected MBR with a clean one can repair the hard drive. Similarly, restoring the infected boot record with a clean one can repair floppy disks. After restoring the MBR and boot record, the data can be accessed. The infected files still need to be repaired.
An infected hard drive may not always boot up even to a clean boot floppy. In this case, the MBR has been corrupted beyond the PC's ability to recognize the hard drive. To fix this problem, you can boot to an early version of DOS, like 3.x. Then, you can use disk utility programs to repair the hard drive.
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.