Strong and Efficient Cache Side-Channel Protection using Hardware Transactional Memory


Daniel Gruss, Graz University of Technology, Graz, Austria; Julian Lettner, University of California, Irvine, USA; Felix Schuster, Olya Ohrimenko, Istvan Haller, and Manuel Costa, Microsoft Research, Cambridge, UK


Cache-based side-channel attacks are a serious problem in multi-tenant environments, for example, modern cloud data centers. We address this problem with Cloak, a new technique that uses hardware transactional memory to prevent adversarial observation of cache misses on sensitive code and data. We show that Cloak provides strong protection against all known cache-based side-channel attacks with low performance overhead. We demonstrate the efficacy of our approach by retrofitting vulnerable code with Cloak and experimentally confirming immunity against state-of-the-art attacks. We also show that by applying Cloak to code running inside Intel SGX enclaves we can effectively block information leakage through cache side channels from enclaves, thus addressing one of the main weaknesses of SGX.

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@inproceedings {203672,
author = {Daniel Gruss and Julian Lettner and Felix Schuster and Olya Ohrimenko and Istvan Haller and Manuel Costa},
title = {Strong and Efficient Cache {Side-Channel} Protection using Hardware Transactional Memory},
booktitle = {26th USENIX Security Symposium (USENIX Security 17)},
year = {2017},
isbn = {978-1-931971-40-9},
address = {Vancouver, BC},
pages = {217--233},
url = {},
publisher = {USENIX Association},
month = aug

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