High resolution and stealthy attacks and their variants such as Flush+Reload, Flush+Flush, Prime+Probe, Spectre and Meltdown have completely exposed the vulnerabilities in Intel’s computing architecture over the past few years. Mitigation techniques against such attacks are not very effective for two reasons: 1) Most mitigation techniques protect against a specific vulnerability and do not take a system-wide approach, and 2) they either completely remove or greatly reduce the performance benefits of resource sharing. In this work, we argue in favor of detection-based protection, which would help apply mitigation only after successful detection of the attack at runtime. As such, detection would serve as the first line of defense against such attacks. However, for a detection based protection strategy to be effective, detection needs to be highly accurate, to incur minimum system overhead at runtime, should cover a large set of attacks and be capable of early stage detection, i.e., at the very least before the attack is completed. We propose a machine learning based side-channel attack (SCA) detection tool, called WHISPER that satisfies the above mentioned design constraints. WHISPER uses multiple machine learning models in an Ensemble fashion to detect SCAs at runtime using behavioral data of concurrent processes, that are collected through hardware performance counters (HPCs). Through extensive experiments with different variants of state-of-the-art attacks, we demonstrate that the proposed tool is capable of detecting a large set of known attacks that target both computational and storage parts in computing systems. We present experimental evaluation of WHISPER against Flush+Reload, Flush+Flush, Prime+Probe, Spectre and Meltdown attacks. The results are provided under variable system load conditions and stringent evaluation metrics comprising detection accuracy, speed, system-wide performance overhead and distribution of error (i.e., False Positives & False Negatives). Our experiments show that WHISPER can detect a large and diverse attack vector with more than 99% accuracy at a reasonably low performance overhead.
Somewhat Homomorphic Encryption (SHE) schemes allow to carry out operations on data in the cipher domain. In a cloud computing scenario, personal information can be processed secretly, inferring a high level of confidentiality. For many years, practical parameters of SHE schemes were overestimated, leading to only consider the FFT algorithm to accelerate SHE in hardware. Nevertheless, recent work demonstrates that parameters can be lowered without compromising the security [1]. Following this trend, this work investigates the benefits of using Karatsuba algorithm instead of FFT for the Fan-Vercauteren (FV) Homomorphic Encryption scheme. The proposed accelerator relies on an hardware/software co-design approach, and is designed to perform fast arithmetic operations on degree 2,560 polynomials with 135 bits coefficients, allowing to compute small algorithms homomorphically. Compared to a functionally equivalent design using FFT, our accelerator performs an homomorphic multiplication in 11.9 ms instead of 15.46 ms, and halves the size of logic utilization and registers on the FPGA.
The evolution of manycore systems, forecasted to feature hundreds of cores by the end of the decade calls for efficient solutions for design space exploration and debugging. Among the relevant existing solutions the well-known gem5 simulator provides a rich architecture description framework. However, these features come at the price of prohibitive simulation time that limits the scope of possible explorations to configurations made of tens of cores. To address this limitation, this paper proposes a novel trace-driven simulation approach for efficient exploration of manycore architectures.
Cache Side Channel Attacks (SCAs) have gained a lot of attention in the recent past. Since, these attacks exploit the caching hardware vulnerabilities, they are fast and dangerous. Detection of cache side channel attacks is an important step towards mitigating against such hostile entities. Researchers have already proposed different techniques to detect cache side channel attacks. This paper provides a detailed survey of literature related to the state-of-the-art detection techniques for cache based side channel attacks. We identify a set of important characteristics that can be used to characterize a CSCA (cache side channel attack) detection technique. We use the identified features to compare and contrast the most important detection techniques and provide the important observations. We also identify some of the challenges that the research community will have to resolve in future to improve the efficiency of cache side channel detection techniques. To the best of our knowledge, this is the first work to do such a study. We believe that this paper will prove useful to researchers in the area of systems security.
This paper presents experimental evaluation and comparative analysis on the use of various Machine Learning (ML) models for detecting Cache-based Side Channel Attacks (CSCAs) in Intel's x86 architecture. The paper provides performance evaluation of ML models based on run-time detection accuracy, speed, computational overhead, and distribution of error in terms of false positives and false negatives. Experiments are performed using state-of-the-art CSCAs namely; Flush+Reload and Flush+Flush attacks, under realistic load conditions on RSA and AES crypto-systems. The paper provides quantitative & qualitative analysis of at least 12 ML models being used for CSCA detection for the first time.