Practice Resources
- 
https://blog.elearnsecurity.com/free-resources-to-legally-practice-ethical-hacking.html
 - 
http://pwnable.kr
 - https://pwnable.tw
 - https://ctflearn.com
 - https://www.root-me.org
 - https://www.hackthebox.eu
 - https://www.hacking-lab.com
 - https://microcorruption.com
 - https://crackmes.one
 - 
https://ctflearn.com/
 - 
http://hackyourselffirst.troyhunt.com
 - http://github.com/bkimminich/juice-shop
 - http://hack.me
 - http://HackThisSite.org
 - http://github.com/Hackademic/hackademic
 - http://try2hack.nl
 - http://slavehack.com
 - http://hackthis.co.uk
 - http://hackxor.sourceforge.net/cgi-bin/index.pl
 - http://sourceforge.net/projects/peruggia
 - http://github.com/psiinon/bodgeit
 - http://bonsai-sec.com/en/research/moth.php
 - http://enigmagroup.org
 
Google CTFs
- https://github.com/google/google-ctf
 
CrackMe sites
- http://crackmes.de/
 
Writing a CrackMe
(anti-debugging and anti reverse-engineering tricks) - https://www.pelock.com/articles/how-to-write-a-crackme-for-a-ctf-competition - https://github.com/PELock/CrackMeZ3S-CTF-CrackMe-Tutorial/
Writeups
- Metasploitable: https://hackercool.com/metasploitable/
 - Binary/HTB: https://0xrick.github.io/categories/
 - HTB Writeups: https://www.peerlyst.com/posts/how-to-break-into-tr0ll-1-machine-writeup-spirited-wolf
 
Vulnhub
Pinky’s Palace V4
- https://medium.com/@lijnk/pinkys-palace-v4-writeup-1cef1dab06ff