ItwasourpleasuretoholdtheInternationalWorkshoponSecurity2006(IWSEC 2006) this year in Kyoto and to publish the proceedings as a volume of the Lecture Notes in Computer Science series. The workshop was our ?rst trial in that two major academic society groups on security in Japan, viz. ISEC and CSEC, jointly organized it; ISEC is a te- nical group on information security of the Institute of Electronics, Information and Communication Engineers (IEICE), and CSEC is a special interest group on computer security of the Information Processing Society of Japan (IPSJ). It was Ryoichi Sasaki, the...

This book constitutes the proceedings of the 4th International Conference on Science of Cyber Security, SciSec 2022, held in Matsu, Japan in August 2022. The 36 full papers presented in this volume were carefully reviewed and selected from 88 submissions. The papers are organized in the following topical sections: blockchain and applications; cryptography and applications; network security; cyber-physical system; malware; mobile system security; system and web security; security in financial industry; social engineering and personalized security; privacy and anonymity.