Management of false try counter in portable data medium involves writing entry into security buffer corresponding to new counter state after false try, so value written to counter during restoration

摘要

The data medium has a security buffer for storing data that are to be written at least into the non-volatile memory for a restoration process triggered by a restart of the data medium. The method involves writing an entry into the security buffer with a value corresponding to a new counter state after a false try, so that this value is written into the counter during a restoration process, and carrying out the protected process. The false try counter monitors the number of false tries in carrying out a protected process. The data medium has a security buffer for storing data that are to be written at least into the non-volatile memory for a restoration process triggered by a restart of the data medium. The method involves writing an entry into the security buffer with a value corresponding to a new counter state after a false try, so that this value is written into the counter during a restoration process, and carrying out the protected process. Independent claims are also included for the following: (a) a data medium, especially a chip card or module with a processor core for implementing the inventive method (b) and a computer program product for causing a processor core to implement the inventive method.