Spies and hackers can now eavesdrop on conversations from 82 feet away just by analysing the vibration patterns in a hanging light bulb. The hack, dubbed “lamphone,” costs less than $1,000 and requires a laptop, a telescope and an electro-optical sensor. This novel side-channel attack has been developed by researchers at Ben-Gurion University of the Negev and Weizmann Institute of Science.
Researchers performed the hack by placing three telescopes around 80 feet away from the lightbulb and placed Thorlabs PDA100A2 electro-optical sensors on their eyepiece. A 16-bit ADC NI-9223 card was then used to obtain the voltage from the optical sensor which was sent to LabVIEW script for processing. The target lightbulb was a 12-Watt LED bulb.
The sound recovered was then played back to some audio discovery apps, e.g., Shazam, which uses complex sound detection algorithms coupled with artificial intelligence. This method was accurate enough to detect music tracks as well as the song and chatters in the room.
While most of our household utilities of the likes of smart TV, smartphone, laptops and tablets, smart fridge, smart microwave, are hackable, the thing that our light bulbs don’t even have to be smart for the spying to work makes it a game changer.
Researchers also found that LED bulbs make for better eavesdropping tools with a signal-to-noise ratio of around 6.3x that of an incandescent bulb and 70x that of a fluorescent bulb. The full findings will be virtually presented at the 2020 Black Hat USA security conference, sometime between August 1–6.