Type your comment> @deltaivctf said:
I am also stuck on this, I followed all of the stuff that was taught in the tutorial and I have been reading and watching all different kinds of exploits and have learned a lot of stuff but none of them seem to pertain to this challenge. I note what blueprismo said but I am not sure what I am missing
I don’t want to give you a direct answer at it’s against the rules. But check these points:
1- did you get a reverse shell = (rs)? How?
2- With this rs, what user are you logged in?
3- you know how sticky bits work, right?
4- find the file with the sticky bit set.
5- remember when you are inside gdb and run " $(python -c blablabla)" it’s the same as executing the script with the parameter, as follows: ‘./script $(python -c blablabla)’
I can’t help you more, check these points and I’m sure you will pass 
keep me updated.