Definition - What does Macro Virus mean?
A macro virus is a computer virus that replaces a macro, which is what enables a program to work and instigates a designated group of actions and commands. When these actions and commands are replaced by a virus, this can cause significant harm to a computer.
Macro viruses can be built into sophisticated applications such as those present in word processors in order to run programs so that they can be launched automatically. Because macro viruses replace prompt commands, word processors are especially vulnerable to these types of viruses. The language is built into the macros in order to hijack the commands, including necessary actions like opening up a document. Thus, through the simple action of opening a document, a macro virus can be launched. Macro viruses may be spread through email attachments, modems and on the Internet, networks, and disks.
Techopedia explains Macro Virus
By and large, macro viruses are launched by simply opening a document. The macro virus is initially embedded in one document or a few documents, but it can spread to other documents within the same computer, as well reaching out to other computers through shared documents. Unfortunately, not all macro viruses can be detected by anti-virus software, although there are some good products available that can be used to detect them.
One of the most notorious and damaging macro viruses was developed by David Smith in 1999. Some reports state that he named the macro virus Melissa after a Miami stripper bearing the same name. Once a Word documented was downloaded, it would replicate itself into the user’s email and send automated messages to the first 50 addresses which, in turn, would infect recipients’ emails as well as their recipients, and so on.
Smith was sentenced to 10 years, but served 20 months in prison and was fined $5,000; the damage he caused totaled $80 million and affected more than 1 million computers.