This book constitutes the proceedings of the 19th International Conference on Provable and Practical Security, ProvSec 2025, which took place in Yokohama, Japan, during October 10–12, 2025.

The 22 full papers, 3 short papers and 5 posters included in this book were carefully reviewed and selected from 72 submissions. They were organized in topical sections as follows: digital signature; post-quantum cryptography; machine learning security and privacy; cryptographic protocol; searchable encryption; cryptanalysis; distributed system and blockchain security; short papers; and posters.

set programming; functional programming; languages, methods and tools; and declarative

solutions.