The Ultrasonic Jammer

Ultrasonic cyberattacks represent an emerging threat vector capable of exfiltrating information even from high-security systems. Modern computing devices equipped with integrated speakers and microphones can generate ultrasonic emissions that may be exploited for covert communication. Previous studies have demonstrated that malicious software can utilize ultrasonic audio channels to establish communication links between otherwise isolated systems, enabling data leakage from air-gapped environments by relaying information through acoustic signals. Experimental results have shown that data can be transmitted at rates of up to 20 bits per second over distances of approximately 18 meters (60 feet), facilitating the covert transfer of sensitive information. Moreover, networks of compromised devices can be chained together to bridge air-gapped systems and transmit data to external receivers. The work presents a real-time system that detects and disrupts covert ultrasonic communication used for hidden data transmission. The authors demonstrate the threat by building an ultrasonic Morse-code channel capable of transmitting data up to 20 meters. To counter this, they develop a mitigation framework using external acoustic hardware that detects ultrasonic signals and jams them with high-power interference. The system effectively prevents data exfiltration, showing strong performance at distances of 5, 10, and 15 meters across different environments.