We're going back, way back... to the days where people actually BROWSED FTP sites and downloaded philes! What: These are a series of binary challenges. Some may be asking for a password, validating a registration key, or some other challenge where you are assigned the task of figuring out how it works. No source will be provided, nor any debugging symbols. It will be akin to a released binary which one may encounter in real life (outside of a development environment). Why: The goal is to teach people how to reverse binaries. This has a myriad of practical uses, some legal and some are not. How you use the information is up to you. These are just intended to help you develop the skills. What do I win: If you solve the challenge, you get that nice feeling of accomplishment. You also likely learned something, which is the real reward. If you get neither of these, then you can either try a higher level, or move on to a more difficult challenge like frank^2's seven four challenges: http://argolith.ms/?p=sevenfour Format: The files marked as "spoiler" are answers. This will vary from one challenge to another, but it'll typically include the source code and at least one solution to the challenge. It may have a file with hints on where to look (specific offsets, unusual input, etc.). If you are in it to learn, you won't look at this file until you've mastered the challenge. Compatibility: I am going to try to make all the challenges compatible with both *nix and Windows. As far as I know, the *nix versions should also run on OSX and *BSD. I'm primarially working on the Linux side of things, so that's where I'm reversing, debugging, decompiling, etc. I compile it on a windows VM for people who work on the windows side of things, but I do not do much testing there. I basically just run it and make sure it executes. If you can reverse on one OS, you should be able to handle another. The major changes don't come along until switching architectures. The only architecture I support is x86 simply because that's all I have. You are welcome to download the source, blindly compile it and try it on an ARM, SPARC, or whatever else you might have. Other: The name "facile-binary-challenges" was not a choice, it was a lack of options (and creativity). Sorry to disappoint, but there's no cool story behind it.