This book constitutes the refereed proceedings of the 25th International Conference, ICISC 2022, held in Seoul, South Korea, during November 30–December 2, 2022. The 24 full papers included in this book were carefully reviewed and selected from 69 submissions. They were organized in topical sections as follows: Public Key Encryption with Hierarchical Authorized Keyword Search, Implicit Key-stretching Security of Encryption Schemes.