Skimming off wireless electromagnetic signals for surveillance isn’t a new idea. It’s a vulnerability referred to as TEMPEST (Transient ElectroMagnetic Pulse Emanation STandard, a very awkward backronym) with roots in espionage going all the way back to World War II. But as a digital transmission with at least some level of encryption using the HDCP system, HDMI cables weren’t thought to be particularly susceptible to it. The researcher’s AI algorithm-assisted method of attack (which they’re calling “Deep-TEMPEST”) opens up some very disturbing possibilities.
The researchers claim that this system, or functionally identical alternatives, are already being used by state-level spies and industrial espionage agents. The sophisticated nature of the technique and the need to be at least somewhere in the vicinity of the target system means that it’s unlikely to affect regular users. But any government agency or large company with sensitive data should be wary and might want to look into EM-shielding measures—and that goes double for any of their employees who work from home.