Depending on the attacker's approach, data can be retrieved at a rate of 10 to 1,000 bits per second.
Researchers at Ben-Gurion University of the Negev, Israel, have published a paper titled PowerHammer: Exfiltering Data from Physically Isolated Computers over an Electrical Network. This article describes how to install malware that regulates the use of the central processor and creates electric current fluctuations that can modulate and encode data.
Depending on the attacker's approach, data can be retrieved at a rate of 10 to 1,000 bits per second. The speed will be higher if the attacker manages to gain access to the computer's power cable, and lower if the attacker can only connect to the building's electrical network.
The PowerHammer malware, developed by the researchers, increases CPU utilization by targeting kernels that are not currently being used by user operations (to avoid detection). To modulate the data, specialists used the frequency-shift keying method, which allows transmitting frequencies with a certain amplitude of oscillations as 1 and 0.
“The data is modulated, encoded and transmitted on top of the current fluctuations in current, and then redirected and propagated through the power lines. This phenomenon is known as "jamming", - added the experts.
