In recent years, mobile devices have become essential tools for daily communication activities and social network interactions for billions of people all around the world. As such devices contain a plethora of private and sensitive information, they have become popular targets of attacks to harm users' privacy, among which a passive attack called side-channel analysis. The side-channels are a physical phenomenon that can be measured from both inside or outside a device. They are mostly due to the user interaction with a mobile device, but also to the context in which the device is used, hence they can reveal sensitive user information among which audio content from private conversations. This talk focuses on eavesdropping attacks by measuring the sound-induced vibrations via two distinct approaches. The first attack focuses on the vibration produced by the built-in mobile device's loudspeaker via the accelerometer sensor. The second attack utilizes a mmWave radar to reconstruct the audio within a room from the minute vibrations on surrounding objects. Differently from other state-of-the-art methods, both these attacks can achieve eavesdropping with unconstrained vocabulary.
21/03/2024