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arXiv · 1906.02282

Enhancing Gradient-based Attacks with Symbolic Intervals

Shiqi Wang·Yizheng Chen·Ahmed Abdou·Suman Jana
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Abstract

Recent breakthroughs in defenses against adversarial examples, like adversarial training, make the neural networks robust against various classes of attackers (e.g., first-order gradient-based attacks). However, it is an open question whether the adversarially trained networks are truly robust under unknown attacks. In this paper, we present interval attacks, a new technique to find adversarial examples to evaluate the robustness of neural networks. Interval attacks leverage symbolic interval propagation, a bound propagation technique that can exploit a broader view around the current input to locate promising areas containing adversarial instances, which in turn can be searched with existing gradient-guided attacks. We can obtain such a broader view using sound bound propagation methods to track and over-approximate the errors of the network within given input ranges. Our results show that, on state-of-the-art adversarially trained networks, interval attack can find on average 47% relatively more violations than the state-of-the-art gradient-guided PGD attack.

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BibTeXRIS

Shiqi Wang, Yizheng Chen, Ahmed Abdou, Suman Jana. 2019-06-05. Enhancing Gradient-based Attacks with Symbolic Intervals. https://arxiv.org/abs/1906.02282

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