Air-Gapped Devices Can Send Covert Morse Signals via Network Card LEDs
Aug 24, 2022
A security researcher who has a long line of work demonstrating novel data exfiltration methods from air-gapped systems has come up with yet another technique that involves sending Morse code signals via LEDs on network interface cards ( NICs ). The approach, codenamed ETHERLED , comes from Dr. Mordechai Guri , the head of R&D in the Cyber Security Research Center in the Ben Gurion University of the Negev in Israel, who recently outlined GAIROSCOPE , a method for transmitting data ultrasonically to smartphone gyroscopes. "Malware installed on the device could programmatically control the status LED by blinking or alternating its colors, using documented methods or undocumented firmware commands," Dr. Guri said. "Information can be encoded via simple encoding such as Morse code and modulated over these optical signals. An attacker can intercept and decode these signals from tens to hundreds of meters away." A network interface card, also known as a netwo...
