This book constitutes the refereed proceedings of the 13th International Workshop on Security, IWSEC 2018, held in Sendai, Japan, in September 2018. The 18 regular papers and 2 short papers presented in this volume were carefully reviewed and selected from 64 submissions. They were organized in topical sections named: Cryptanalysis, Implementation Security, Public-Key Primitives, Security in Practice, Secret Sharing, Symmetric-Key Primitives, and Provable Security.

This book constitutes the refereed proceedings of the 13th International Workshop on Security, IWSEC 2018, held in Sendai, Japan, in September 2018. The 18 regular papers and 2 short papers presented in this volume were carefully reviewed and selected from 64 submissions. They were organized in topical sections named: Cryptanalysis, Implementation Security, Public-Key Primitives, Security in Practice, Secret Sharing, Symmetric-Key Primitives, and Provable Security.