Process for protecting a security module, and associated security module

A process for protecting a security module (8) designed to cooperate with a data processing device (1), the module comprising data processing means (9, 2) and data storage means (10;

• 3, 4) and being designed to execute a set of operations including at least one sensitive operation (23), characterized in that it includes the steps comprised of:
• executing, at the time of each execution of the sensitive operation and upstream from the latter, a first supplementary sequence of operations (22) intended to activate signaling means, and downstream from said sensitive operation, a second supplementary sequence of operations (24) intended to deactivate said signaling means;
• counting each interrupted attempt for which the sensitive operation has been initiated but not executed, so that the signaling means have been initially activated but not subsequently deactivated, in order to define a number of interrupted attempts detected NRS;
• defining a number of interrupted attempts authorized NRSA;
• comparing, at the time of each execution of the sensitive operation and upstream from the latter, said number of interrupted attempts detected NRS to said number of interrupted attempts authorized NRSA;
• and
• in the case where said number of interrupted attempts detected NRS is greater than said number of interrupted attempts authorized NRSA, inhibiting the execution of the sensitive operation.