X97M.Barisada.A

SUMMARY

This Microsoft Excel macro virus replicates when an infected spreadsheet window is closed. On April 24th at 14:00 (2PM), the virus prompts you to answer a question or it will clear the cells in the current spreadsheet. However, the viral payload does not work as intended.

Protection

• Virus Definitions (Intelligent Updater) June 5, 2000

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 Trigger: On April 24th at 14:00 (2PM)
• Payload: Copies itself as Hjb.xls in the Excel startup directory (generally XLSTART)
• Modifies Files: The virus intends to clear the cells of all open spreadsheets

Distribution

• Distribution Level: Low
• Target of Infection: Microsoft Excel spreadsheets

TECHNICAL DETAILS

This virus adds a Visual Basic Application (VBA) module to infected spreadsheets and adds its viral code to every worksheet in the spreadsheet file.

The infection routine is triggered on deactivation of an infected worksheet in Excel. An active worksheet is deactivated when you edit another worksheet window.

The virus creates the file Hjb.xls and inserts it in the Excel startup directory (usually OfficeXLSTART). This causes the viral code to load when Excel starts.

The virus triggers a routine intended to clear the contents of the currently opened Excel file on April 24 at 14:00. You are required to answer one of two yes-or-no questions.

The first question is:

What is the Sword Which Karl Styner(=Gray Scavenger) used? Answer: Barisada.

The answer to this question is no. If you answer incorrectly, you are given one more opportunity to prevent the virus payload from triggering.

The second question is:

Summoning Xavier is the Ultimate Magic. Right?

The answer to this question is yes. Answering either question correctly prevents the virus from clearing the currently opened Excel file.

As previously noted, however, this function of the macro virus does not work as intended.

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

Delete the file Hjb.xls from the system. Norton AntiVirus detects and repairs files infected with this virus