Malware and your Mac
While malware for macOS is rare, it’s good to be aware of the risk it poses
MalWare takeS a number of forms. Viruses are one of the most insidious, capable of hiding on a computer and replicating themselves into unrelated files, causing corruption. Spyware can be even worse, relaying your data or keystrokes to hackers. Don’t panic, though: to do their dirty work they have to be able to execute code, and macOS is very good at preventing this.
In practice, there’s little risk from malware unless you type in an admin user account’s username and password to give it permission to install, or choose to bypass Gatekeeper to run it. This is where Trojans come in. Like the wooden horse, they look like one thing — an app you want to use — but contain something less friendly.
Protect and SUrvive
Apps on the Mac App Store are approved by Apple and can only run “sandboxed”, meaning their ability to affect your system is limited even if they contain malicious code. But from other sources fake installers may be hard to spot. Don't run anything unless you trust its source and it’s up to date.
If you like to try a lot of apps, or you’re setting up a Mac for someone who isn’t a confident computer user and might be confused into authorizing actions they shouldn’t, there are comprehensive security monitoring packages. Intego’s well– established Mac Premium Bundle ($70/year, intego.com) offers a free trial. If you prefer a completely free solution, Avast Security (avast.com) blocks viruses, spyware and Trojans, and can scan your Mac for any already present. The $59.99 Pro version protects against ransomware, which locks up your files. Again, you needn’t fear this if you avoid authorizing malware, but it’s yet another reason to have backups — ideally separate from your Mac. Never install anti–malware apps from search results: they may be fake, plague you with ads, or open the door to hackers.
Worried something may be on your Mac already? Malwarebytes (bit.ly/mfmy) will check; the free version cleans infected files; the Premium version ($29.99/year) can stop attacks in their tracks. Objective–See (objective-see.com) offers free tools to check what Mac apps are up to.