Quote:Imagine someone hacking into an Amazon Alexa device using a laser beam and then doing some online shopping using that person account. This is a scenario presented by a group of researchers who are exploring why digital home assistants and other sensing systems that use sound commands to perform functions can be hacked by light.
 
The same team that last year mounted a signal-injection attack against a range of smart speakers merely by using a laser pointer are still unraveling the mystery of why the microelectro-mechanical systems (MEMS) microphones in the products turn the light signals into sound.
 
Researchers at the time said that they were able to launch inaudible commands by shining lasers – from as far  as 360 feet – at the microphones on various popular voice assistants, including Amazon Alexa, Apple Siri, Facebook Portal, and Google Assistant.
 
“[B]y modulating an electrical signal in the intensity of a light beam, attackers can trick microphones into producing electrical signals as if they are receiving genuine audio,” said researchers at the time.
Now, the team– Sara Rampazzi, an assistant professor at the University of Florida; and Benjamin Cyr and Daniel Genkin, a PhD student and an assistant professor, respectively, at the University of Michigan — has expanded these light-based attacks beyond the digital assistants into other aspects of the connected home.