The 40th Symposium on Cryptography and Information Security (SCIS) was held at Hybrid (Zoom, Kokurakita-ku, Kitakyushu-shi, Fukuoka-ken) for four days from January 24 to 27, 2023. The presentations included a proposal of a cryptographic infrastructure for blockchain, a security evaluation of next-generation cryptography, security in automatic driving, risk assessment for business applications of metaverse, and a proposal of a new model for authentication, etc. The presentations were meaningful in that they provided practical knowledge for social implementation. During the Q&A session, there was a lively exchange of opinions both face-to-face and via Zoom.