Weikeng Chen (UC Berkeley), Raluca Ada Popa (UC Berkeley)

File-sharing systems like Dropbox offer insufficient privacy because a compromised server can see the file contents in the clear. Although encryption can hide such contents from the servers, metadata leakage remains significant. The goal of our work is to develop a file-sharing system that hides metadata---including user identities and file access patterns.

Metal is the first file-sharing system that hides such metadata from malicious users and that has a latency of only a few seconds. The core of Metal consists of a new two-server multi-user oblivious RAM (ORAM) scheme, which is secure against malicious users, a metadata hiding access control protocol, and a capability sharing protocol.

Compared with the state-of-the-art malicious-user file-sharing scheme PIR-MCORAM (Maffei et al.'17), which does not hide user identities, Metal hides the user identities and is 500x faster (in terms of amortized latency) or 10^5x faster (in terms of worst-case latency).

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Data-Driven Debugging for Functional Side Channels

Saeid Tizpaz-Niari (University of Colorado Boulder), Pavol Černý (TU Wien), Ashutosh Trivedi (University of Colorado Boulder)

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Not All Coverage Measurements Are Equal: Fuzzing by Coverage...

Yanhao Wang (Institute of Software, Chinese Academy of Sciences), Xiangkun Jia (Pennsylvania State University), Yuwei Liu (Institute of Software, Chinese Academy of Sciences), Kyle Zeng (Arizona State University), Tiffany Bao (Arizona State University), Dinghao Wu (Pennsylvania State University), Purui Su (Institute of Software, Chinese Academy of Sciences)

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Post-Quantum Authentication in TLS 1.3: A Performance Study

Dimitrios Sikeridis (The University of New Mexico), Panos Kampanakis (Cisco Systems), Michael Devetsikiotis (The University of New Mexico)

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HYPER-CUBE: High-Dimensional Hypervisor Fuzzing

Sergej Schumilo (Ruhr-Universität Bochum), Cornelius Aschermann (Ruhr-Universität Bochum), Ali Abbasi (Ruhr-Universität Bochum), Simon Wörner (Ruhr-Universität Bochum), Thorsten Holz (Ruhr-Universität Bochum)

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