Breaking a Chaotic Cryptographic Scheme Based on Composition Maps

TL;DR

This paper critically analyzes a recent chaotic cryptographic scheme based on composition maps, revealing its vulnerabilities to differential attacks and inefficiencies, thereby questioning its security and practicality.

Contribution

The paper demonstrates that the scheme can be broken with a differential attack and highlights the inadequacies of the composition maps as secure random number sources.

Findings

Scheme is vulnerable to differential attack with limited plaintexts.

The scheme lacks plaintext sensitivity.

Composition maps are ineffective as secure random number generators.

Abstract

Recently, a chaotic cryptographic scheme based on composition maps was proposed. This paper studies the security of the scheme and reports the following findings: 1) the scheme can be broken by a differential attack with $6+\lceil\log_L(MN)\rceil$ chosen-plaintext, where $MN$ is the size of plaintext and $L$ is the number of different elements in plain-text; 2) the scheme is not sensitive to the changes of plaintext; 3) the two composition maps do not work well as a secure and efficient random number source.