This book constitutes the refereed proceedings of the 18th International Workshop on Security, IWSEC 2023, which took place as a hybrid event in Yokohama, Japan, during August 29–31, 2023. This event was held in hybrid mode. The 14 full papers presented in this book were carefully reviewed and selected from 47 submissions. They were organized in topical sections as follows: System and Hardware Security; Symmetric Key Cryptography; Public Key Cryptography; Zero Knowledge Proofs; and Card Based Cryptography.

This book constitutes the refereed proceedings of the 16th International Workshop on Security, IWSEC 2021, held in Tokyo, Japan in September 2021. The conference was held virtually due to COVID-19 pandemic. The 14 regular papers and 3 short paper presented in this volume were carefully reviewed and selected from 37 submissions. They were organized in topical sections named: Lattice-Based Cryptography; System Security; Multiparty Computation; Machine Learning and Security; Post-quantum Cryptography; Symmetric-key Cryptography; Game Theory and Security.

This book constitutes the refereed proceedings of the Second International Workshop on Security, IWSEC 2007, held in Nara, Japan, October 29-31, 2007. The 30 revised full papers presented were carefully reviewed and selected from 112 submissions. The papers are organized in topical sections on subjects including Software and Multimedia security, Public-key cryptography, Network security, E-commerce and Voting, Operating systems, and Security and Information management.

This book constitutes the refereed proceedings of the 8th International Workshop on Security, IWSEC 2013, held in Okinawa, Japan, in November 2013. The 20 revised selected papers presented in this volume were carefully reviewed and selected from 63 submissions. They are organized in topical sections named: software and system security, cryptanalysis, privacy and cloud computing, public key cryptosystems, and security protocols.

This book constitutes the refereed proceedings of the 6th International Workshop on Security, IWSEC 2011, held in Tokyo, Japan, in November 2011. The 14 revised full papers presented in this volume were carefully reviewed and selected from 45 submissions. They address all current issues in information and computer security such as foundations of security, security in networks and ubiquitous computing systems, and security in real life applications. The papers are organized in topical sections on software protection and reliability; cryptographic protocol; pairing and identity based signature; malware detection; mathematical and symmetric cryptography; public key encryption.

This book constitutes the refereed proceedings of the First International Workshop on Security, IWSEC 2006, held in Kyoto, Japan in October 2006. The 30 revised full papers presented were carefully reviewed and selected from 147 submissions.