Method of modifying secrets included in a cryptographic module, notably in an unprotected environment

A method of modifying secrets included in a cryptographic module on a card, the cryptographic module including a set version number that corresponds to a set of a plurality of secrets in the cryptographic module, wherein the cryptographic module:

• indicates whether a loading of a secret is either successful, or invalid;
• and
• allows reading of a version number for each secret;
• wherein the method comprises the steps of:
• assigning a predetermined number to the set version number of the set of secrets of the cryptographic module, if the set version number of the set of secrets is equal to a version number that requires a set of new secrets to be loaded, in order to indicate that the cryptographic module is being reloaded;
• for each secret in the set of secrets, loading a corresponding new secret and a version number of said new secret if a version number of the secret is different from the version number of the corresponding new secret to be loaded;
• assigning a set version number of the set of new secrets to the set version number of the set of secrets of the cryptographic module;
• wherein the set version number of the set of secrets of the cryptographic module on the card is recorded in a file of the cryptographic module of the card accessible via an immutable secret.