A CCA2 Secure Variant of the McEliece Cryptosystem

TL;DR

This paper presents the first McEliece cryptosystem construction secure against chosen ciphertext attacks in the standard model, enhancing its security while maintaining efficiency.

Contribution

It introduces a novel CCA2-secure variant of the McEliece cryptosystem based on recent techniques, filling a gap in cryptographic security standards.

Findings

First CCA2-secure McEliece cryptosystem in the standard model

Maintains efficiency of encryption and decryption

Provides enhanced security against chosen ciphertext attacks

Abstract

The McEliece public-key encryption scheme has become an interesting alternative to cryptosystems based on number-theoretical problems. Differently from RSA and ElGa- mal, McEliece PKC is not known to be broken by a quantum computer. Moreover, even tough McEliece PKC has a relatively big key size, encryption and decryption operations are rather efficient. In spite of all the recent results in coding theory based cryptosystems, to the date, there are no constructions secure against chosen ciphertext attacks in the standard model - the de facto security notion for public-key cryptosystems. In this work, we show the first construction of a McEliece based public-key cryptosystem secure against chosen ciphertext attacks in the standard model. Our construction is inspired by a recently proposed technique by Rosen and Segev.