A team of researchers from the National University of Singapore and the University of Maryland has published a paper with a title of ‘Spying with your robot vacuum cleaner: eavesdropping via lidar sensors‘ that explains exactly what how your robot vacuum can eavesdrop conversations. Under the supervision of Prof. Jun Han, Sriram Sami took the lead in this research aided by Yimin Dai, Sean Rui Xiang Tan and Nirupam Roy.
Abstract: Eavesdropping on private conversations is one of the most common yet detrimental threats to privacy. A number of recent works have explored side-channels on smart devices for recording sounds without permission. This paper presents LidarPhone, a novel acoustic side-channel attack through the lidar sensors equipped in popular commodity robot vacuum cleaners.
The core idea is to repurpose the lidar to a laser-based microphone that can sense sounds from subtle vibrations induced on nearby objects. LidarPhone carefully processes and extracts traces of sound signals from inherently noisy laser reflections to capture privacy sensitive information (such as speech emitted by a victim’s computer speaker as the victim is engaged in a teleconferencing meeting; or known music clips from television shows emitted by a victim’s TV set, potentially leaking the victim’s political orientation or viewing preferences). We implement LidarPhone on a Xiaomi Roborock vacuum cleaning robot and evaluate the feasibility of the attack through comprehensive real world experiments.
We use the prototype to collect both spoken digits and music played by a computer speaker and a TV sound bar, of more than 30k utterances totaling over 19 hours of recorded audio. LidarPhone achieves approximately 91% and 90% average accuracies of digit and music classifications, respectively.