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arXiv · 2007.07354

Extending Coggia-Couvreur Attack on Loidreau's Rank-metric Cryptosystem

Anirban Ghatak
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Abstract

A recent paper by Coggia and Couvreur presents a polynomial time key-recovery attack on Loidreau's encryption scheme, based on rank-metric codes, for some parameters. The secret matrix component of Loidreau's scheme is chosen over a defining subspace of the field associated with the rank-metric code. We partially extend the Coggia-Couvreur attack to deal with the case when the defining subspace has dimension greater than 2.

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Anirban Ghatak. 2020-07-14. Extending Coggia-Couvreur Attack on Loidreau's Rank-metric Cryptosystem. https://doi.org/10.1007/s10623-021-00972-7

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