A practical attack to Bouftass's cryptosystem

TL;DR

This paper presents a practical attack on Bouftass's cryptosystem, exploiting lattice reduction techniques to compromise its security based on the difficulty of inverting a specific modular function.

Contribution

The paper introduces a novel lattice-based attack method that effectively breaks Bouftass's cryptosystem, demonstrating its vulnerabilities.

Findings

The attack successfully recovers private keys in the cryptosystem.

Lattice reduction techniques are effective against the protocol.

The security assumptions of Bouftass's scheme are challenged.

Abstract

Recently, a new fast public key exchange protocol was presented by S. Bouftass. The protocol is based on the difficulty of inverting the function $F(x)=\lfloor (zx \mod 2^p)/ 2^q \rfloor$. In this paper, we describe a practical attack against this protocol based on Closest Vector Problem (CVP) and Gaussian lattice reduction.