Debugger-driven Embedded Fuzzing

Embedded Systems – the hidden computers in our lives – are deployed in the billionths and are already in the focus of attackers. They pose security risks when not tested and maintained thoroughly. In recent years, fuzzing has become a promising technique for automated security testing of programs, which can generate tons of test inputs for a program. Fuzzing is hardly applied to embedded systems, because of their high diversity and closed character. During my research I want tackle that gap in fuzzing embedded systems – short: “Embedded Fuzzing”. My goal is to obtain insights of the embedded system during execution, by using common debugging interfaces and hardware breakpoints to enable guided fuzzing in a generic and widely applicable way. Debugging interfaces and hardware breakpoints are available for most common microcontrollers, generating a potential industry impact. Preliminary results show that the approach covers basic blocks faster than blackbox fuzzing. Additionally, it is source code agnostic and leaves the embedded firmware unaltered.