SECURITY TOKEN, METHOD FOR EXECUTING COMMAND IN SECURITY TOKEN, AND COMPUTER PROGRAM

PROBLEM TO BE SOLVED: To provide a security token, when correcting an error of data using an ECC (Error Correction Code), capable of transferring data whose error has been corrected, to another area.SOLUTION: The security token includes: an NVM (Non-Volatile Memory) 30 for storing data in block units with a predetermined bit length; ECC control means 11, when writing the data in the NVM 30, calculating the ECC for every block used for storing the data, storing the ECC in the NVM 30 associated with the block used for storing the data, when a power supply is applied, verifying the ECC for every block, and storing the verification result associated with the block; and command execution means 10, when receiving an access command to access to the data stored in the NVM 30 and if the verification result of the ECC corresponding to the block used for storing the data subject to an access indicates that an error of the data has been corrected, transfers the data subject to the access to a free area of the NVM 30 and then executes the access command.