Preventing Cache-Based Side-Channel Attacks in a Cloud Environment

Cloud computing is a unique technique for outsourcing and aggregating computational hardware needs. By abstracting the underlying machines cloud computing is able to share resources among multiple mutually distrusting clients. While there are numerous practical benefits to this system, this kind of resource sharing enables new forms of information leakage such as hardware side-channels. In this paper, we investigate the usage of CPU-cache based side-channels in the cloud and how they compare to traditional side-channel attacks. We go on to demonstrate that new techniques are necessary to mitigate these sorts of attacks in a cloud environment, and specify the requirements for such solutions. Finally, we design and implement two new cache-based side-channel mitigation techniques, implementing them in a state-of-the-art cloud system, and testing them against traditional cloud technology.