Countermeasure method for an electronic component implementing an elliptic curve cryptography algorithm

A computer program product comprising computing instructions stored on a non-transitory computer storage medium and when the computing instructions are executed by one or more processors, configure the one or more processors to implement a countermeasure method for an electronic component implementing a public-key cryptography algorithm on an elliptic curve E defined over a field K, the countermeasure method comprising implementing one or more iterations of a scalar multiplication operation to obtain a point [k]P from a point P of the curve E and from an integer k using at least one critical point, an electrical consumption of the electronic component being dependent on the value taken by said at least one critical point, wherein the countermeasure method further comprises:

• providing at least one power of an element c of K, said element c being constant, non-null and different from one;
• initializing the coordinates of said at least one critical point to predefined values;
• and implementing said scalar multiplication operation, the coordinates associated with said at least one critical point being modified at each iteration of said scalar multiplication operation by multiplying at least one of the coordinates of the critical point by said at least one power of the element c obtained in the providing, wherein the countermeasure method provides protection against an attack.