Abstract. Java Cards have been threatened so far by attacks using ill-formed applications which assume that the application bytecode is not verified. This assumption remained realistic as long as the bytecode verifier was commonly executed off-card and could thus be bypassed. Nevertheless it can no longer be applied to the Java Card 3 Connected Edition context where the bytecode verification is necessarily performed on-card. Therefore Java Card 3 Connected Edition seems to be immune against this kind of attacks. In this paper, we demonstrate that running ill-formed application does not necessarily mean loading and installing ill-formed application. For that purpose, we introduce a brand new kind of attack which combines fault injection and logical tampering. By these means, we describe two case studies taking place in the new Java Card 3 context. The first one shows how ill-formed applications can still be introduced and executed despite the on-card bytecode verifier. The second example leads to the modification of any method already installed on the card into any malicious bytecode. Finally we successfully mount these attacks on a recent device, emphasizing the necessity of taking into account these new threats when implementing Java Card 3 features.

Abstract. In this article we present the first Combined Attack on a Java Card targeting the APDU buffer itself, thus threatening both the security of the platform and of the hosted applications as well as the privacy of the cardholder. We show that such an attack, which combines malicious application and fault injection, is achievable in practice on the latest release of the Java Card specifications by presenting several case studies taking advantage for instance of the well-known GlobalPlatform and (U)SIM Application ToolKit.