1.GOT of system <- main
2.GOT of snprintf <- system@plt
3.system('/bin/sh')

[read more](http://note.taqini.space/#/ctf/ByteBanditsCTF-2020/?id=fmt-me)

Original writeup (http://taqini.space/2020/04/13/ByteBanditsCTF-Pwn-Writeup/#fmt-me).