Biblio

Hardware IPs are assumed to be roots-of-trust in complex SoCs. However, their design and security verification are still heavily dependent on manual expertise. Extensive research in this domain has shown that even cryptographic modules may lack information flow security, making them susceptible to remote attacks. Further, when an SoC is in the hands of the attacker, physical attacks such as fault injection are possible. This paper introduces EISec, a novel tool utilizing symbolic execution for exhaustive analysis of hardware IPs. EISec operates at the pre-silicon stage on the gate level netlist of a design. It detects information flow security violations and generates the exhaustive set of control sequences that reproduces them. We further expand its capabilities to quantify the confusion and diffusion present in cryptographic modules and to analyze an FSM's susceptibility to fault injection attacks. The proposed methodology efficiently explores the complete input space of designs utilizing symbolic execution. In short, EISec is a holistic security analysis tool to help hardware designers capture security violations early on and mitigate them by reporting their triggers.

The USB protocol has become ubiquitous, supporting devices from high-powered computing devices to small embedded devices and control systems. USB's greatest feature, its openness and expandability, is also its weakness, and attacks such as BadUSB exploit the unconstrained functionality afforded to these devices as a vector for compromise. Fundamentally, it is virtually impossible to know whether a USB device is benign or malicious. This work introduces FirmUSB, a USB-specific firmware analysis framework that uses domain knowledge of the USB protocol to examine firmware images and determine the activity that they can produce. Embedded USB devices use microcontrollers that have not been well studied by the binary analysis community, and our work demonstrates how lifters into popular intermediate representations for analysis can be built, as well as the challenges of doing so. We develop targeting algorithms and use domain knowledge to speed up these processes by a factor of 7 compared to unconstrained fully symbolic execution. We also successfully find malicious activity in embedded 8051 firmwares without the use of source code. Finally, we provide insights into the challenges of symbolic analysis on embedded architectures and provide guidance on improving tools to better handle this important class of devices.