Palaiologos' CTF

I decided to make a few CTF tasks suitable both for beginners, as well as some for advanced programmers with background in reverse engineering. I'll try to upload CTF's featuring most interesting and popular technologies. Every challenge has a score bar showing my rating of a challenge (id est, how hard it is). I'm not publishing flags and reference answers, but if you complete the tasks, feel free to post your writeup and share it. If you feel confident enough, you can skip some low-rated challenges. I hope you'll find these challenges valuable, and you'll learn something while solving both harder, or easier ones. I'll try to include a platform near each of the challenges, as well as a tiny hint for the harder ones.

I'm not interested in making it a full-featured CTF website to track user scores, solve time, etc..., because it's not a timed CTF that I plan to end.

0/10DownloadCTF 0
A pretty simple and straightforward challenge for beginners.
2/10DownloadCTF 1
A bit more difficult task, featuring encryption.
5/10DownloadCTF 2
Quite hard task if you don't have CS background; however it's perfectly solvable if you understand the task correctly. Will probably require some computation time.
3/10DownloadCTF 3
Exposes to a known vulnerability (for which a builtin check has been disabled).
4/10DownloadCTF 4
For a lazy person, the challenge is scored four. For someone overestimating it, it's six. Try to find a key to the simplicity!
8/10DownloadCTF 5
Quite challenging task; may take some time to get started with the program. All I see is just subtraction!
1/10DownloadCTF 6
An easy and obvious exploitation task
2/10DownloadCTF 7
A simple exploitation challenge.
3/10DownloadCTF 8
Yet another exploitation task, but this time with more advanced security measures enabled.
4/10DownloadCTF 9
Simple shellcode-related task.
5/10DownloadCTF 10
A bit harder shellcode task, play it smart!