Towards more secure EMV purchase transactions

New Security Protocols for Offline Point-of-Sale Machines

“…We suggest that the actor P needs to generate an electronic signature SignP, using its sk(P), in order to authenticate itself to C. The verification of the authenticity of P, in order to respond to ReqP, will be performed by another actor as follows [8]:…”

“…• C is identified by IdC in the database of IB and not by the PAN as in the EMV protocol [8]. IdC is not a sensitive information as the PAN, it does not present a risk if it is sent in clear because it does not allow to make purchases.…”

“…During a purchase transaction, each proposed solution is represented in a set of security messages that are exchanged between the involved actors. For each of our proposals, we suggest dividing these security messages into three phases (Initialization (Phase 1), Authentication of the Client (Phase 2), Authentication of C and P (Phase 3)) instead of four phases as in the EMV security protocol: as specified in section 1, it is essential to refer to our work [8] in order to clarify the roles of the EMV actors and the description of the EMV phases.…”

“…Indeed, the description of the EMV protocol is non-trivial, due to the high complexity of the EMV specifications in more than 1000 pages in [2][3][4][5][6][7]. Therefore, in our previous work [8], we introduced a synthetic overview of this protocol: it is essential to refer to this work in order to clarify the roles of the EMV actors and the description of the EMV exchanged messages (EMV phases).…”

“…Fig. 1: EMV payment system [8] Accordingly, in our previous work [8], we proposed a new security solution that solves these two EMV weaknesses in the case where P can communicate with the banking network and then it is in the "online" connectivity mode. In this paper, we are interested in solving the two EMV weaknesses in the case where P is in the "offline" connectivity mode and then it cannot communicate with the banking network.…”