SCATTER: A New Dimension in Side-Channel

Abstract

Side-channel techniques have well progressed over the last few years, leading to the creation of a variety of statistical tools for extracting the secrets used in cryptographic algorithms. Such techniques are taking advantage of the side-channel traces collected during the executions of secret computations in the product. Noticeably, the vast majority of side-channel attacks requires the traces have been aligned together beforehand. This prerequisite turns out to be more and more challenging in the practical realisation of attacks as many devices include hardware or software countermeasures to increase this difficulty. This is typically achieved applying random jittering or random executions with fake operations. In this paper, we introduce scatter, a new attack which has the potential to tackle most of the alignment issues. scatter brings a new dimension to improve the efficiency of existing attacks and opens the door to a large set of potential new attack techniques. The effectiveness of scatter has been proven on both simulated traces and real word secure products. As a result, scatter is a new side-channel technique particularly powerful when the trace alignment represents an issue, or even when considering low-cost attacks, as the requirements in terms of equipment and expertise are significantly reduced.

Spatial Dependency Analysis to Extract Information from Side-Channel Mixtures

“…Then we propose to investigate two alternative approaches to analyze them efficiently. First, as jitter spreads the information over multiple time-samples, we applied the Scatter technique [TGWC18], which gathers several sources (i.e. X t ) into the same statistical distribution to counteract jitter.…”

“…Some other techniques demonstrated that they can tackle the alignment problem by removing the time factor, at least partially. This is the case of frequency based analyses [BBB + 16], distribution based analyses [TGWC18] or deep learning techniques using Convolutional Neural Networks [PSB + 18]. They all have their pros and cons, and should certainly all be considered.…”

Power Side-Channel Attack Analysis: A Review of 20 Years of Study for the Layman

“…Several techniques, such as fake cycles insertion, unstable clocking, or random delays [49], can be employed to induce alignment problems. To counter these, signal processing can be employed in many cases to correct and align traces [50][51][52]. Other countermeasures seek to add noise or employ filtering circuitry [53].…”

The role of metrology in the cyber-security of embedded devices

“…The implementation of this type of attack simply consists of two main phases: (i) the acquisition of power traces and (ii) a statistical analysis. With regard to the actual statistical analysis, different types of attacks can be distinguished: Simple Power Analysis, Differential Power Analysis [12], Correlation Power Analysis [13], and scatter analysis [14]. Moreover, machine learning-based approaches to data analysis are gaining more and more interest due to their capability of decoding patterns generated by complex systems [15]- [17].…”