Researchers at the University of Washington have demonstrated how smart devices can be hijacked to steal information using little more than a speaker and a microphone.

CovertBand Software Uses Sound Waves to Track Movement

In an academic paper titled, “CovertBand: Activity Information Leakage Using Music,” the researchers described a system they created, dubbed CovertBand, which takes over smart devices by tricking users into installing an Android app. The software then uses the AudioRecord API to track human movement using sound waves picked up near a laptop, tablet or speaker.

As The Daily Mail reported, CovertBand’s ability to listen in on people is surprisingly strong. Third parties could track movements through walls, for example, and distinguish whether someone is standing or sitting. CovertBand plays signals at 18 to 80 kilohertz that reflect off people and objects via the AutoTrack API.

Those using the system could be monitoring activities from the other side of the world. Most significantly, the technology involved is largely made up of sound-playing components that are already in most smart devices today.

Spyware Potential for Smart Devices

Although there is no evidence that malicious actors are using software like CovertBand today, the researchers’ work has several possible applications, The Hacker News suggested. Taking over smart devices would be far less conspicuous, for example, than some of the tools that have traditionally been deployed for surveillance purposes.

There are other, less nefarious but perhaps equally invasive uses for CovertBand. SC Magazine noted that the system could be used to detect when a consumer is close to a smart device just by using a streaming app’s embedded music library. This capability could be leveraged to determine the effectiveness of ads or play targeted advertisements.

There are some basic methods to prevent CovertBand, GeekWire said. This includes playing music that would essentially jam the system’s signal. There may also be ways to make a room soundproof, but that would require knowledge that someone might try such an attack.

Given the prevalence of smart devices, particularly in residential homes that lack adequate protection, the research pointed to a potentially widespread vulnerability. Security managers should take note of CovertBand’s capabilities and take appropriate measures to secure smart devices.