Fault attacks described in cryptographic papers mostly apply to cryptographic algorithms‚ yet such attacks may have an impact on the whole system in a smart card. In this paper‚ we describe what can be achieved nowadays by using fault attacks in a smart card environment. After studying several ways of inducing faults‚ we describe attacks on the most popular cryptosystems and we discuss the problem of induced perturbations in the smart card environment. Finally we discuss how to find appropriate software countermeasures.

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.

No abstract

No abstract

Up to now devices in charge of performing secure transactions mainly remained limited regarding their functionalities. However the trend has recently gone towards an increasing integration of features and technologies, which could potentially represent a source of additional threats. This article introduces an innovative attack exploiting advanced functionalities and offering unrivalled opportunities. This attack targets specifically the multithreaded systems featuring network capabilities. By the way of a network flooding we show how a process can be interrupted at the precise time a sensitive operation is being executed. This interruption aims at subsequently modifying the execution context and consequently breaking the sensitive operation. The practical feasibility of this attack is illustrated on a Java Card 3.0 Connected Edition platform. This description reveals that going through with the full attack scenario is not obvious. However this apparent complexity must not conceal the potential breach, which may significantly alter any application running on the system. Finally the goal of this work is to emphasize that the increasing products complexity may generate new security issues rather than to highlight a specific weakness on released products.