The Ads That Freeze Your Screen, Then Sell You a Fake Help Line

Security researchers say Google ads have been carrying a tech support scam with a cruel bit of timing: the ad freezes the screen on both Windows and Mac devices, then displays messages urgently instructing the user to phone a bogus call center for help. Anyone who called the number was pushed to pay hefty fees, grant remote access to their device, or divulge personal information. The panic is the hook, and the fake help line is the till.