Communications in Computer and Information Science

This book constitutes the conference proceedings of the 4th International Conference on Security and Privacy, ICSP 2025, held in Rourkela, India, during December 5–7, 2025.The 14 full papers in this book were carefully reviewed and selected from 52 submissions. They were organized in topical sections as follows: Mathematical Foundation of Cryptography, Authentication Key Management and Machine Learning in Cybersecurity.