## CryptoDB

### Paper: Cryptanalysis of the Repaired Public-key Encryption Scheme Based on the Polynomial Reconstruction Problem

Authors: Jean-Sébastien Coron URL: http://eprint.iacr.org/2003/219 Search ePrint Search Google At Eurocrypt 2003, Augot and Finiasz proposed a new public-key encryption scheme based on the polynomial reconstruction problem. The scheme was subsequently broken by Coron, who showed that given the public-key and a ciphertext, one could recover the corresponding plaintext in polynomial time. Recently, Augot, Finiasz and Loidreau published on the IACR eprint archive a reparation of the cryptosystem. The reparation is based on the trace operator, and is resistant against the previous attack. However, we describe a new cryptanalysis of the repaired scheme. Given the public-key and a ciphertext, we can still recover the corresponding plaintext in polynomial time. Our technique is a variant of the Berlekamp-Welsh algorithm, and works very well in practice, as for the proposed parameters, we recover the plaintext in less than 8 minutes on a single PC.
##### BibTeX
@misc{eprint-2003-11932,
title={Cryptanalysis of the Repaired Public-key Encryption Scheme Based on the Polynomial Reconstruction Problem},
booktitle={IACR Eprint archive},
keywords={public-key cryptography / Cryptanalysis, Augot and Finiasz cryptosystem.},
url={http://eprint.iacr.org/2003/219},
note={ coron@clipper.ens.fr 12338 received 10 Oct 2003, last revised 13 Oct 2003},
author={Jean-Sébastien Coron},
year=2003
}