Benoit Gonzalvo

JTAG Combined Attack - Another Approach for Fault Injection

The combined attacks are widely spread in the domain of smart cards and microcontrollers but they have not been yet democratized on System on chip (SoC) such as those that can be found in smart phones, tablets and automotive systems. The main reason behind this is the complexity to inject a fault at the right place and at the right time to make these attacks effective on such devices. However for development and debug, these devices provide new tools that could be considered as potential attacks path. Its the case of the JTAG debug tool which is present on today most electronic devices. The improper use of this latter is already known but in this paper we present a new misuse of this one: the JTAG as a fault injection tool. Through an example, we explain how this tool can be used to perform a combined attack.