In PlaidCTF 2018 - shop challenge, there is a buffer overflow vulnerability that allows us to leak heap and libc base addresses. Finally, we can overwrite put@GOT with one gadget in order to execute /bin/sh. This is an interesting heap exploitation challenge to learn bypassing protections like NX, Canary, and ASLR in x86_64 binaries.

Original writeup (https://github.com/sajjadium/ctf-writeups/tree/master/PlaidCTF/2018/shop).