Abstract:

This paper addressed the evaluation of the security of a lightweight stream cipher algorithm based on a time-varying mutually coupled dual chaotic system, which was crucial for securing data in resource-constrained environments such as the Internet of things and mobile communications. The article selected the mixed integer linear programming method as an analytical tool to construct a mathematical model of the algorithm, and revealed the maximum linear correlation coefficients of the algorithm under different modes of operation, ranging from 2^-54 to 2^-26, by optimally solving the model. This finding suggests that the algorithm is vulnerable in terms of correlation, and an attacker may be able to crack the algorithm by exhaustively enumerating up to 110 bits of the initial key, which is much less complex than the complexity of exhaustively enumerating its 128-bit initial key. This paper not only provides a quantitative assessment of the security of this algorithm, but also emphasizes the importance of correlation analysis in cryptographic design and the effectiveness of the mixed integer linear programming technique in the security assessment of cryptographic algorithms. Overall, the research in this paper is of great theoretical and practical significance in advancing the security analysis and design of lightweight cryptographic algorithms, and provides strong theoretical support for data security in resource-constrained environments.

Key words: chaos-based stream cipher, linear analysis, mixed integer linear programming