[Resource Topic] 2020/292: LWE with Side Information: Attacks and Concrete Security Estimation

Welcome to the resource topic for 2020/292

LWE with Side Information: Attacks and Concrete Security Estimation

Authors: Dana Dachman-Soled, Léo Ducas, Huijing Gong, Mélissa Rossi


We propose a framework for cryptanalysis of lattice-based schemes, when side information—in the form of ``hints’'— about the secret and/or error is available. Our framework generalizes the so-called primal lattice reduction attack, and allows the progressive integration of hints before running a final lattice reduction step. Our techniques for integrating hints include sparsifying the lattice, projecting onto and intersecting with hyperplanes, and/or altering the distribution of the secret vector. Our main contribution is to propose a toolbox and a methodology to integrate such hints into lattice reduction attacks and to predict the performance of those lattice attacks with side information. While initially designed for side-channel information, our framework can also be used in other cases: exploiting decryption failures, or simply exploiting constraints imposed by certain schemes (LAC, Round5, NTRU). We implement a Sage 9.0 toolkit to actually mount such attacks with hints when computationally feasible, and to predict their performances on larger instances. We provide several end-to-end application examples, such as an improvement of a single trace attack on Frodo by Bos et al (SAC 2018). In particular, our work can estimates security loss even given very little side information, leading to a smooth measurement/computation trade-off for side-channel attacks.

ePrint: https://eprint.iacr.org/2020/292

Talk: https://www.youtube.com/watch?v=wCaLcbWnwDI

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .