Wm.Outlaw

SUMMARY

The Outlaw Word macro virus is one of the few known polymorphic macro viruses. It is believed to have originated in Germany. This virus infects when a user attempts to edit an infected document. Outlaw then copies itself to the global template, 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: 20th of every month
• Payload: Plays "Laugh.Wav" and adds "You are infected with Outlaw A virus from Nightmare Joker " to document.
• Modifies Files: Adds "You are infected with Outlaw A virus from Nightmare Joker " to document

Distribution

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

TECHNICAL DETAILS

On the 20th of the month, on 32-bit Windows systems running Word 7.0 or later, this virus drops a file on the user’s hard drive called LAUGH.WAV, and plays it. At this time, it will also insert the text

You are infected with
Outlaw
A virus from Nightmare Joker

in a large font, and maximize the current document window.

This virus achieves its polymorphism by changing its macro names. An Outlaw infection consists of three macros. Each macro name has five characters - the first one is a letter, and the last four are digits.

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.