Of all the cyber threats facing businesses today, computer viruses are among the most problematic. Not only can they steal data; they are called “viruses” because they have the innate ability to replicate and spread — just like pathogenic viruses faced by us humans.

There are many different types of computer viruses, however, one of which is macro. Macro viruses can replicate and spread like all other computer viruses, but they are designed in a specific way that distinguishes them from the rest. What is a macro computer virus exactly?

Overview of Macro Computer Viruses

A macro computer virus is a type of self-replicating malicious program that’s written in a macro coding language. Without getting into its technical specifications, a macro is a series of multiple commands that’s embedded within a program. From word processors and spreadsheet editors to photo-editing and accounting software, countless programs contain macros. Macro viruses consist of malicious macros that run within otherwise legitimate programs.

Because they run within legitimate programs, macro computer viruses are oftentimes overlooked by antivirus software and other traditional cybersecurity measures. As previously mentioned, many programs use macros. Microsoft Word files, for instance, often contain multiple macros. Therefore, antivirus software may assume that macro is legitimate when it’s actually malicious.

How Macro Computer Viruses Infect Hosts

Macro computer viruses infect hosts through a particular program. Normally, infection occurs when a host downloads a legitimate-looking file — which contains the macro computer virus — and then opens the file in a particular program.

Email is a common vector of transmission for macro computer viruses. You may download a file attachment believing it’s a legitimate file, only for it to infect your computer once you open it.

Tips to Protect Against Macro Computer Viruses

Although they are difficult to detect, macro computer viruses still leave a digital footprint. As a result, performing a deep scan of your computer using the right antivirus software can lower the risk of infection.

Since most macro computer viruses infect hosts through email, you should use caution when downloading file attachments. Always verify the sender’s identity before downloading a file attachment. If you aren’t confident about the sender’s identity, don’t download it.

If your computer runs Windows, make sure it has the latest version. Macro computer viruses are often embedded in Microsoft Office programs, so Microsoft regularly updates its Windows operating system (OS) to protect against them. If your computer runs an outdated version, though, it will remain vulnerable to infection.