Avast Antivirus – Mac is Protected Do Macs Have Built-in Antivirus Software? So do you need antivirus software on your Mac, or does the computer have built-in antivirus protection? The answer is more complicated than you might think. But these days, bad actors are creating malware that targets Macs and can take over your computer and steal your personal financial information. For many years, most Mac users assumed that their computers were safe from the viruses that attacked PCs.