Billy Fung


Reverse Engineering

Billy Fung / 2015-11-23

Breaking things is fun

One of the things I enjoy doing is taking things apart and figuring out how they work at a very basic level. Reverse engineering is a very broad field, and often requires a stubborn attitude towards trying to hack and bash at something until either it gives up, or you give up. These days I’ve been playing around with the CTF game called Microcorruption. The premise is to figure out how to unlock an electronic lock by breaking apart it’s software.

The website makes it easier to understand low level code without having to build a debugger and grab memory off devices, which is how it would probably be done in the real world. So the point of the game is to figure out exploits in the code that will make the lock open. The difficulty progressively gets harder, so the first few locks are simple and relatively easy to figure out. The skills learned include understanding how assembly and C code works together within a physical device. This is a very low level programming of where passwords are stored, and how different techniques might be used to exploit it.

Doing this stuff is akin to what you see the hackers doing on television shows when they ’re able to force password protected to do their bidding. Things like stack overflow and stack smashing can be utilized. So far I’ve been having tons of fun with the site, but it definitely gets frustrating at times.