For the past 2-3 weeks my Mac is opening unknown websites in Safari . They are telling me to download antivirus and sometimes opening your website telling that they have detected virus . What should I do ?
MacBook Air 13", 10.13
First, run Malwarebytes.
There's been some dreck installed on this Mac. Probably some sketchy cleaner or sketchy anti-malware or sketchy cracked app, or some such. Probably something free, too. The folks that offered that freebie are now looking to up-sell you, and to further profit.
There's a reasonable possibility that the perpetrators of the app have already uploaded what data they can extract from the files and mail and contacts and the rest of the data, but—if that happened here—that's already happened, and there's little you can do other than watching your credit cards, and expecting to see further email scams arriving.
MalwareBytes can usually exterminate the gremlin, though that's not certain.
Unknown websites opening automatically
