Google ads served a scam that seems to freeze Windows and Mac screens and demands you call for help. It's a bluff: hold Escape, never call.

Picture a county fair where somebody rents a booth, hangs a sign that says your truck is on fire, and hands you a phone number to call. That's about what security firm Netskope found running through Google's ad network, Ars Technica reports. From Aug. 31 to Sept. 14, Netskope watched users from 619 of its customer organizations click malicious Google ads that led to a tech support scam. The ads ran on high-traffic maps, weather, real estate, document-hosting and sports sites, across at least 284 legitimate publisher sites and more than 250 Google Ads campaign IDs. Click one, and the browser seems to seize up: the warning fills the screen, the address bar disappears, Escape and other keys stop working, sounds play and pages lag, all urging you to call a bogus call center. Callers were pushed to pay hefty fees, grant remote access or give up personal information. Netskope blocked the content for its customers, but it sees only a tiny sliver of internet activity, so far more people were likely exposed. "Nothing on the computer is actually locked, but in the moment it is convincing enough to push people toward the scam," the firm said. Google said, "We have zero tolerance for scams," and that it is investigating and will act against accounts that violate its policies. My take: the fix is simpler than the scare. Press and hold the Escape key for several seconds to drop out of full screen, then close the tab. Or use Control-Shift-Escape to open Task Manager on Windows, or Command-Option-Escape on a Mac, and quit the browser. Reopen it without restoring the old session. And never call the number. No legitimate company will ever tell you to call because you're infected. Tape that note next to the family computer.