The field of cybersecurity is obsessed with preventing and detecting breaches, finding every possible strategy to keep hackers from infiltrating your digital inner sanctum. But Mordechai Guri has spent the last four years fixated instead on exfiltration: How spies pull information out once they’ve gotten in. Specifically, he focuses on stealing secrets sensitive enough to be stored on an air-gapped computer, one that’s disconnected from all networks and sometimes even shielded from radio waves. Which makes Guri something like an information escape artist.
More, perhaps, than any single researcher outside of a three-letter agency, Guri has uniquely fixated his career on defeating air gaps by using so-called “covert channels,” stealthy methods of transmitting data in ways that most security models don’t account for. As the director of the Cybersecurity Research Center at Israel’s Ben Gurion University, 38-year-old Guri’s team has invented one devious hack after another that takes advantage of the accidental and little-noticed emissions of a computer’s components—everything from light to sound to heat.
Guri and his fellow Ben-Gurion researchers have shown, for instance, that it’s possible to trick a fully offline computer into leaking data to another nearby device via the noise its internal fan generates, by changing air temperatures in patterns that the receiving computer can detect with thermal sensors, or even by blinking out a stream of information from a computer hard drive LED to the camera on a quadcopter drone hovering outside a nearby window. In new research published today, the Ben-Gurion team has even shown that they can pull data off a computer protected by not only an air gap, but also a Faraday cage designed to block all radio signals.
Read More: WIRED