How to Tell If Your Mac Has Malware
The myth that Macs don't get malware is decades out of date. The good news is detection is straightforward.
Real signs of infection: browser homepages that change themselves, search engines you didn't choose, pop-ups outside the browser, unfamiliar apps in the menu bar, or sustained CPU usage when nothing is open.
Open System Settings, General, Login Items. Anything you don't recognize, especially in the Allow in Background section, is a candidate for removal.
Run a single scan with Malwarebytes for Mac (free version is fine). Don't install three different antivirus tools — they conflict and slow the Mac more than any malware would.
If suspicious behavior persists after cleanup, the malware may have installed launch agents or daemons that survive normal removal. That requires deeper inspection. I do these cleanups in person and explain how it got in so you can avoid the same trap next time.
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