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arXiv · 2105.07692

Cryptanalysis of Semidirect Product Key Exchange Using Matrices Over Non-Commutative Rings

Christopher Battarbee·Delaram Kahrobaei·Siamak F. Shahandashti
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Abstract

It was recently demonstrated that the Matrix Action Key Exchange (MAKE) algorithm, a new type of key exchange protocol using the semidirect product of matrix groups, is vulnerable to a linear algebraic attack if the matrices are over a commutative ring. In this note, we establish conditions under which protocols using matrices over a non-commutative ring are also vulnerable to this attack. We then demonstrate that group rings $R[G]$ are examples of non-commutative rings that satisfy these conditions.

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Christopher Battarbee, Delaram Kahrobaei, Siamak F. Shahandashti. 2021-05-17. Cryptanalysis of Semidirect Product Key Exchange Using Matrices Over Non-Commutative Rings. https://arxiv.org/abs/2105.07692

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