This post is a quick intro about the first concepts of reversing firmware. It is not a methodology that can be used to reverse any firmware due to the nature and the variety of devices and firmwares available, however the steps and the tools used in this post are a good starting point for who wants to learn more about this matter. In this article I will be reversing a few router firmware.
Reversing firmware can be fun but also very frustrating. There are firmware that can be easily reversed just by using the right tools at the right time, others in which you need to read lines of assembly code, some may come obfuscated and requires extra effort before being reversed.