WM.Divina.A

SUMMARY

WM.Divina.A is a macro virus originating in Italy. The virus resides in the AutoClose macro in Microsoft Word document files and the global template, named NORMAL.DOT.

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: May 21
• Payload: Displays messages on screen
• Deletes Files: Threatens to format hard drive, although there is no coding in the virus to do this.

Distribution

• Distribution Level: Low
• Target of Infection: Microsoft Word documents

TECHNICAL DETAILS

A user’s machine becomes infected when an infected Microsoft Word document is closed. Closing the document infects the NORMAL.DOT file. Once this file is infected, all other documents subsequently edited are infected as they are closed. On occasion, WM.Divina.A infects all open template files without the user closing them.

On May 21st, WM.Divina.A displays two dialog boxes.

The first dialog box contains the following text:

Divina is the best!

zio Massimo

The first dialog box contains the following text (translated from Italian):

Happy birthday to Divina: Let’s have a great party! I won’t format your hard disk... The Divina virus is executing

At other times, the virus displays messages in English, suggesting that the user’s hard drive is infected, and that the problem can be solved by a low-level format of the hard disk.

Divina does not contain any code that formats the hard disk.

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.