Papa brought me a packed present! let's open it.

Download : http://pwnable.kr/bin/flag

This is reversing task. all you need is binary

Nana told me that buffer overflow is one of the most common software vulnerability. 
Is that true?

Download : http://pwnable.kr/bin/bof
Download : http://pwnable.kr/bin/bof.c

Running at : nc pwnable.kr 9000

Daddy told me about cool MD5 hash collision today.
I wanna do something like that too!

ssh col@pwnable.kr -p2222 (pw:guest)

Mommy! what is a file descriptor in Linux?

* try to play the wargame your self but if you are ABSOLUTE beginner, follow this tutorial link:
https://youtu.be/971eZhMHQQw

ssh fd@pwnable.kr -p2222 (pw:guest)