In this study, we investigate the emerging threat of inaudible acoustic attacks targeting digital voice assistants, a critical concern given their projected prevalence to exceed the global population by 2024. Our research extends the feasibility of these attacks across various platforms like Amazon's Alexa, Android, iOS, and Cortana, revealing significant vulnerabilities in smart devices. The twelve attack vectors identified include successful manipulation of smart home devices and automotive systems, potential breaches in military communication, and challenges in critical infrastructure security. We quantitatively show that attack success rates hover around 60%, with the ability to activate devices remotely from over 100 feet away. Additionally, these attacks threaten critical infrastructure, emphasizing the need for multifaceted defensive strategies combining acoustic shielding, advanced signal processing, machine learning, and robust user authentication to mitigate these risks.

翻译：本研究探究针对数字语音助手的不可听声学攻击这一新兴威胁，鉴于其预计到2024年普及率将超过全球人口，这是一个关键问题。我们的研究将此类攻击的可行性扩展到亚马逊Alexa、安卓、iOS和Cortana等多个平台，揭示了智能设备中的重大漏洞。已识别的十二种攻击向量包括对智能家居设备和汽车系统的成功操控、军事通信的潜在入侵以及关键基础设施安全面临的挑战。我们定量显示，攻击成功率约达60%，且能够在超过100英尺（约30.5米）的远程距离激活设备。此外，这些攻击威胁关键基础设施，凸显了结合声学屏蔽、先进信号处理、机器学习和稳健用户认证的多方面防御策略以缓解这些风险的必要性。