Understanding the Macro Virus

A macro virus is a computer infection written in macro language, which is commonly built into word processing applications.  In general, macros is a series of commands and executions that help automate specific tasks.  Regardless of how they are created, they must be executed by a system able to interpret stored commands.  Some macro systems are actually self-contained utilities while others are built into more advanced applications that allow users to easily repeat a sequence of commands or enable a programmer to customize the application to suite the user's needs. 

What has made some programs vulnerable to the macro virus is a feature that allows macros to be stored in the documents that are edited, processed and saved by the application.  This means that a virus can be easily attached to a document without the user's knowledge and executed upon opening the file.  This provides a mechanism that enables the infection to spread throughout the system. 

How it Functions

A macro virus may be distributed via email, floppy disk, network sharing, a modem and compromised sites on the internet.  Since most macros automatically start when a documented is opened and closed, a macros virus seeks to replace the original with it's malicious code.  From their, the infection tags the replacement code with the same name and functions when the command is executed which happens when a user accesses the file. 

Once opened, the macro virus begins to embed itself within other documents and templates.  It also makes preparations to infect any files that will eventually be created.  Depending on what resources it is able to access, a macro virus can damage other areas of the operating system.  This occurs as the infected documents are shared amongst other users and devices. 

One of the most popular variations of this infection is the Melissa Virus, first detected in 1999.  It spread via email attachment and infected any recipient who opened it.  This virus manipulated the victim's address book and distributed itself to numerous email contacts, enabling it to replicate at an alarming rate. 

A macro virus has the ability to infect nearly any system running word processing software.  This is because it seeks to corrupt that application opposed to the operating system.  The virus has been known to attack computers running Mac OS X, Windows and other platforms that are compatible with Microsoft Word. 

Prevention

Because of the wide spread of macro viruses, it is important to remain cautious of the emails you receive.  Many of the messages waiting in your inbox are attached with financial scams and malicious programs.  By downloading an attachment from these unsolicited messages, a macro virus can be easily installed onto your computer, and from there, the madness begins. 

The best defense against a macro virus is a reliable anti-virus program.  A good scanner will check every file and directory in your system and even scan emails and attachments before you even open them.  This small step is one that can save you a lot of time, money and the frustrations associated with internet threats.