DifFuzz: Differential Fuzzing for Side-Channel Analysis

Abstract

Side-channel attacks allow an adversary to uncover secret program data by observing the behavior of a program with respect to a resource, such as execution time, consumed memory or response size. Side-channel vulnerabilities are difficult to reason about as they involve analyzing the correlations between resource usage over multiple program paths. We present DIFFUZZ, a fuzzing-based approach for detecting side-channel vulnerabilities related to time and space. DIFFUZZ automatically detects these vulnerabilities by analyzing two versions of the program and using resource-guided heuristics to find inputs that maximize the difference in resource consumption between secretdependent paths. The methodology of DIFFUZZ is general and can be applied to programs written in any language. For this paper, we present an implementation that targets analysis of JAVA programs, and uses and extends the KELINCI and AFL fuzzers. We evaluate DIFFUZZ on a large number of JAVA programs and demonstrate that it can reveal unknown sidechannel vulnerabilities in popular applications. We also show that DIFFUZZ compares favorably against BLAZER and THEMIS, two state-of-the-art analysis tools for finding side-channels in JAVA programs.

Efficient Detection and Quantification of Timing Leaks with Neural Networks

“…The works [23,50] Dynamic Analysis for Side-Channel Detections. Dynamic analysis has been used for side-channel detections [38,41,42]. Diffuzz [41] is a fuzzing techniques for finding side channels.…”

“…Dynamic analysis has been used for side-channel detections [38,41,42]. Diffuzz [41] is a fuzzing techniques for finding side channels. The approach extends AFL [1] and KELINCI [28] fuzzers to detect side channels.…”

“…The goal of Diffuzz is to maximize the following objective: δ = |c(p, s 1 ) − c(p, s 2 )|, that is, to find two distinct secret values s 1 , s 2 and a public value p that give the maximum cost (c) difference. The work [41] uses the noninterference notion of side channel leaks. Therefore, they do not quantify the amounts of information leaks.…”

“…Therefore, they do not quantify the amounts of information leaks. The cost function in [41] is the number of byte-code executed, whereas we consider the actual execution time in a fixed environment. Note that our approach can be used with the abstract cost model such as the byte-code executed in a straight-forward fashion.…”

“…Note that our approach can be used with the abstract cost model such as the byte-code executed in a straight-forward fashion. Diffuzz [41] can be combined with our technique to generate inputs and quantify leaks.…”