The following videos are not created by me. They are created by one of my mentors, g0tmi1k. I re-post here for reference. Please credit to g0tmi1k.
To get Kioptrix 4 (Level 1.3) at here.
To find some hints and solutions, please refer to g0tmi1k's blog at here
g0tmi1k find three different ways to compromise the Kioptrix, here you are (Enjoy!!!) :
Local File Inclusion
That's all! See you.