{"678572":{"#nid":"678572","#data":{"type":"event","title":"PhD Defense by Zhengxian He","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003ETitle:\u0026nbsp; \u003C\/strong\u003E\u003Cem\u003ESynthetic Speech Attacks Against Voice Assistants and Defenses\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EDate\/Time\u003C\/strong\u003E: Monday, December 2, 2024, 2:00-4:00 pm EST\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ELocation (in-person):\u003C\/strong\u003E\u0026nbsp;Coda C0908 Home Park\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EZoom Link\u003C\/strong\u003E:\u0026nbsp;\u003Ca href=\u0022https:\/\/gatech.zoom.us\/j\/96401837809?pwd=YMH05b3kK4CpT73a9uNn4GCg6BHI7c.1\u0026amp;from=addon\u0022\u003E\u003Cstrong\u003Ehttps:\/\/gatech.zoom.us\/j\/96401837809?pwd=YMH05b3kK4CpT73a9uNn4GCg6BHI7c.1\u0026amp;from=addon\u003C\/strong\u003E\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EZhengxian He\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EPh.D. Candidate in Computer Science\u003C\/p\u003E\u003Cp\u003ESchool of Cybersecurity and Privacy\u003C\/p\u003E\u003Cp\u003EGeorgia Institute of Technology\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ECommittee:\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EDr. Mustaque Ahamad (Advisor), School of Cybersecurity and Privacy, Georgia Institute of Technology\u003C\/p\u003E\u003Cp\u003EDr. Alexandra Boldyreva, School of Cybersecurity and Privacy, Georgia Institute of Technology\u003C\/p\u003E\u003Cp\u003EDr. Saman Zonouz, School of Cybersecurity and Privacy, Georgia Institute of Technology\u003C\/p\u003E\u003Cp\u003EDr. Frank Li, School of Cybersecurity and Privacy, Georgia Institute of Technology\u003C\/p\u003E\u003Cp\u003EDr. Ashish Kundu, Cisco Research\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EAbstract:\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EVoice assistants have become prevalent in both home and enterprise environments, offering natural and convenient ways to interact with computing devices. However, their growing adoption has also introduced new security vulnerabilities. This dissertation investigates three critical security aspects of voice assistant systems. First, we demonstrate that attackers can synthesize malicious voice assistant commands using limited, unrelated speech samples to bypass currently available speaker verification mechanisms. In fact, they can achieve high success rates even with a lightweight unit-selection speech synthesis \u0026nbsp;technique. Second, we show how malicious commands directed at voice assistants can be used to setup \u0026nbsp;covert channels for data exfiltration from nearby compromised computers. We explore high frequency modulation to make data transfer unnoticeable to humans and characterize \u0026nbsp;the achievable data rates and reliability of such a channel under various conditions. Third, we develop a novel liveness detection method based on harmonic distortion analysis, which leverages physical characteristics of audio reproduction systems to effectively distinguish between live and synthetic commands while maintaining computational efficiency. Through \u0026nbsp;empirical evaluation, we demonstrate the feasibility of synthetic command attacks and the effectiveness of our proposed defense mechanism. Our findings highlight significant security challenges in current voice assistant systems while providing practical approaches for enhancing their security. This research contributes to both the understanding of voice assistant vulnerabilities and the development of countermeasures against attacks that could exploit such vulnerabilities.\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u003Cem\u003ESynthetic Speech Attacks Against Voice Assistants and Defenses\u003C\/em\u003E\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Synthetic Speech Attacks Against Voice Assistants and Defenses"}],"uid":"27707","created_gmt":"2024-11-20 19:00:38","changed_gmt":"2024-11-20 19:01:13","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2024-12-02T14:00:00-05:00","event_time_end":"2024-12-02T16:00:00-05:00","event_time_end_last":"2024-12-02T16:00:00-05:00","gmt_time_start":"2024-12-02 19:00:00","gmt_time_end":"2024-12-02 21:00:00","gmt_time_end_last":"2024-12-02 21:00:00","rrule":null,"timezone":"America\/New_York"},"location":"Coda C0908 Home Park","extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}