Prevent eavesdropping with Audio Diode

Speakers and microphones are devices that attackers can manipulate to either transfer or collect sensitive data. This may lead to data leakage from air gapped systems. We prevent this by making your audio flows unidirectional.

Eavesdropping through speakers is a real threat

The threat of eavesdropping through speakers is real and imminent. Unprotected devices such as headphones and speakers can be easily manipulated by attackers who turn them into microphones. The membranes in your speakers vibrate both when sound-signals are transferred through the cable and when sound waves reach the membrane from the room. Sound waves that reach the membrane turn into a signal and travel backwards into the system. Access to these signals gives hackers the possibility to listen in on classified discussions.

Data leakage from air gapped system

With appropriate audio driver modifications, a speaker can be transformed into a microphone by an attacker's malicious software. The malicious software can then use the system's speakers to transmit data via high-frequency sound waves that are beyond the range audible to the human ear. This means that humans cannot hear or detect the transmission. The transmission is received by a microphone outside the air-gapped system, leading to information leakage.

Prevent eavesdropping with unidirectional audio flows

Audio diodes mitigate the risks of eavesdropping when using peripheral audio devices by enforcing unidirectional audio flow. The Audio Diode functions like a diode, compelling audio signals to travel in only one direction. This means that the audio signals cannot physically travel backward through the Audio Diode. This design prevents hackers from manipulating a speaker or headphone to function as a microphone to capture surrounding conversations, or as a speaker to leak sensitive data.

Stop hackers with low-pass filters

All sounds that pass through the Audio Diode undergo a low-pass filter. This limits audio frequencies to those perceivable by the human ear. Such a measure thwarts hackers from launching attacks by transmitting high-frequency signals to an external hacking device, ensuring your audio devices remain safeguarded against eavesdropping attempts.

Specifics about the Audio Diode

The Audio Diode is connected between your speaker and your device (computer or other). The sound cable is connected as input and another sound cable is connected as output. Depending on the model you may activate and deactivate sound, microphone and camera to match your security needs.

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