A proof of concept test has shown that some smart TVs can be hacked using just common radio signals that can give a hacker control over the television’s camera and mic to view who is viewing.

The UK Daily Mail reported security researcher Rafael Scheel used a radio signal to gain root access to two SmartTVs, both Samsung in this case, but the technology that allows the hack is included in about 90 percent of the sets now available on the European market. The signal embeds malicious commands that remain with the unit even when it is rebooted or undergoes a factory reset.

The signal takes advantage of two known exploits found in the browsers that run in the background while the TV is operating and can be used to control several sets at the same time, reported ARS Technica