An information processing device of the present disclosure includes: a first storage section for reading only that stores first data beforehand, and restricts reading of the first data after a first event; an operation section that performs one or both of encoding and decoding with use of key data, and restricts, after a second event, change of the key data to be used; a second storage section being readable and writeable and including a plurality of storage regions for each of which access conditions are set, the second storage section that restricts change of the access conditions after a third event; and an information processor that controls the first storage section, the operation section, and the second storage section to perform information processing.