In AsisCTF Quals 2018 - Message Me! challenge, we leak libc base address using a Use After Free (UAF) vulnerability. Using the same Use After Free (UAF) vulnerability, we overwrite __malloc_hook by overlapping fastbin chunks. Finally, we trigger __malloc_hook using a Double Free vulnerability on fastbins. This is a good example of Heap Exploitation challenge to understand how to hijack control flow in x64_86 binaries with Canary, NX, and ASLR enabled.

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