Researchers at Ben-Gurion University in Israel have uncovered a new data extraction hole inside air-gapped networks that takes advantage of the blinking LED lights on top of routers to steal data. Using a router with eight LED lights, researchers said, they were able to extract 8000 bits per second of data. The binary extraction of data via a router s blinking lights is capable of stealthily sidestepping firewalls and other air-gap security measures. Researchers acknowledge the attack scenario is theoretical.
Source: https://threatpost.com/blinking-router-leds-leak-data-from-air-gapped-networks/126199/