VibLive: A Continuous Liveness Detection for Secure Voice User Interface in IoT Environment

The voice user interface (VUI) has been progressively used to authenticate users to numerous devices and applications. Such massive adoption of VUIs in IoT environments like individual homes and businesses arises extensive privacy and security concerns. Latest VUIs adopting traditional voice authentication methods are vulnerable to spoofing attacks, where a malicious party spoofs the VUIs with pre-recorded or synthesized voice commands of the genuine user. In this paper, we design VibLive, a continuous liveness detection system for secure VUIs in IoT environments. The underlying principle of VibLive is to catch the dissimilarities between bone-conducted vibrations and air-conducted voices when human speaks for liveness detection. VibLive is a text-independent system that verifies live users and detects spoofing attacks without requiring users to enroll specific passphrases. Moreover, VibLive is practical and transparent as it requires neither additional operations nor extra hardwares, other than a loudspeaker and a microphone that are commonly equipped on VUIs. Our evaluation with 25 participants under different IoT intended experiment settings shows that VibLive is highly effective with over 97% detection accuracy. Results also show that VibLive is robust to various use scenarios.