Gabriel Kaptchuk (Johns Hopkins University), Matthew Green (Johns Hopkins University), Ian Miers (Cornell Tech)

In this work we investigate the problem of achieving secure computation by combining stateless trusted devices with public ledgers. We consider a hybrid paradigm in which a client-side device (such as a co-processor or trusted enclave) performs secure computation, while interacting with a public ledger via a possibly malicious host computer. We explore both the constructive and potentially destructive implications of such systems. We first show that this combination allows for the construction of stateful interactive functionalities (including general computation) even when the device has no persistent storage; this allows us to build sophisticated applications using inexpensive trusted hardware or even pure cryptographic obfuscation techniques. We further show how to use this paradigm to achieve censorship-resistant communication with a network, even when network communications are mediated by a potentially malicious host. Finally we describe a number of practical applications that can be achieved today. These include the synchronization of private smart contracts; rate limited mandatory logging; strong encrypted backups from weak passwords; enforcing fairness in multi-party computation; and destructive applications such as autonomous ransomware, which allows for payments without an online party.

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Daniele Antonioli (Singapore University of Technology and Design (SUTD)), Nils Ole Tippenhauer (CISPA), Kasper Rasmussen (University of Oxford)

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BadBluetooth: Breaking Android Security Mechanisms via Malicious Bluetooth Peripherals

Fenghao Xu (The Chinese University of Hong Kong), Wenrui Diao (Jinan University), Zhou Li (University of California, Irvine), Jiongyi Chen (The Chinese University of Hong Kong), Kehuan Zhang (The Chinese University of Hong Kong)

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Balancing Image Privacy and Usability with Thumbnail-Preserving Encryption

Kimia Tajik (Oregon State University), Akshith Gunasekaran (Oregon State University), Rhea Dutta (Cornell University), Brandon Ellis (Oregon State University), Rakesh B. Bobba (Oregon State University), Mike Rosulek (Oregon State University), Charles V. Wright (Portland State University), Wu-Chi Feng (Portland State University)

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ExSpectre: Hiding Malware in Speculative Execution

Jack Wampler (University of Colorado Boulder), Ian Martiny (University of Colorado Boulder), Eric Wustrow (University of Colorado Boulder)

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