Peng Huang (Zhejiang University), Yao Wei (Zhejiang University), Peng Cheng (Zhejiang University), Zhongjie Ba (Zhejiang University), Li Lu (Zhejiang University), Feng Lin (Zhejiang University), Fan Zhang (Zhejiang University), Kui Ren (Zhejiang University)

With the wide deployment of microphone-equipped smart devices, more and more users have concerns that their voices would be secretly recorded. Recent studies show that microphones have nonlinearity and can be jammed by inaudible ultrasound, which leads to the emergence of ultrasonic-based anti-eavesdropping research. However, existing solutions are implemented through energetic masking and require high energy to disturb human voice. Since ultrasonic noise can only remain inaudible at limited energy, such noise can merely cover a short distance and can be easily removed by adversaries, which makes these solutions impractical. In this paper, we explore the idea of informational masking, study the transmission and coverage constraints of ultrasonic jamming, and implement a highly effective anti-eavesdropping system, named InfoMasker. Specifically, we design a phoneme-based noise that is robust against denoising methods and can effectively prevent both humans and machines from understanding the jammed signals. We optimize the ultrasonic transmission method to achieve higher transmission energy and lower signal distortion, then implement a prototype of our system. Experimental results show that InfoMasker can effectively reduce the accuracy of all tested speech recognition systems to below 50% even at low energies (SNR=0), which is much better than existing noise designs.

View More Papers

BANS: Evaluation of Bystander Awareness Notification Systems for Productivity...

Shady Mansour (LMU Munich), Pascal Knierim (Universitat Innsbruck), Joseph O’Hagan (University of Glasgow), Florian Alt (University of the Bundeswehr Munich), Florian Mathis (University of Glasgow)

Read More

Analysing Adversarial Threats to Rule-Based Local-Planning Algorithms for Autonomous...

Andrew Roberts (Tallinn University of Technology), Mohsen Malayjerdi (Tallinn University of Technology), Mauro Bellone (Tallinn University of Technology), Olaf Maennel (The University of Adelaide), Ehsan Malayjerdi (Tallinn University of Technology)

Read More

Attacks as Defenses: Designing Robust Audio CAPTCHAs Using Attacks...

Hadi Abdullah (Visa Research), Aditya Karlekar (University of Florida), Saurabh Prasad (University of Florida), Muhammad Sajidur Rahman (University of Florida), Logan Blue (University of Florida), Luke A. Bauer (University of Florida), Vincent Bindschaedler (University of Florida), Patrick Traynor (University of Florida)

Read More

Automata-Based Automated Detection of State Machine Bugs in Protocol...

Paul Fiterau-Brostean (Uppsala University, Sweden), Bengt Jonsson (Uppsala University, Sweden), Konstantinos Sagonas (Uppsala University, Sweden and National Technical University of Athens, Greece), Fredrik Tåquist (Uppsala University, Sweden)

Read More