| 摘要 |
PROBLEM TO BE SOLVED: To provide a user authentication device, system, method, and program which have no risk of secret information's leakage even when using the secret information for personal authentication and can safely authenticate the user by combining the secret information. ! SOLUTION: A user authentication device 10 including secret key storage means 31 for associating a secret key with a type of secret information and storing them by user identification information creates a random number; creates designation information for designating secret information to be used for authentication; transmits the created random number and designation information to a client terminal 50; receives a cipher from the client terminal 50 which receives the transmitted random number and designation information, accepts secret information based on the designation information from a user, and encrypts the random number on the basis of the accepted secret information; and authenticates the user by extracting a secret ke |
