circusmonkey404's Security Site

PIcoCTF 2018 – Binary Exploitation - buffer overflow0 Objective: Let's start off simple, can you overflow the right buffer in this program [1]   to get the flag? You can also find it in /problems/buffer-overflow-0_1_316c391426b9319fbdfb523ee15b37db on the shell server. Source [2] . Hints: (1)     How can you trigger the flag to print? (2) If you try to do the math by hand, maybe try and add a few more characters. Sometimes there are things you aren't expecting. Solution:   I started by CDing over to the problem folder Ls shows us a flag file(Which we can’t open) the program and the c code The title tells us this is about a buffer over flow Running the program we get this ./vuln This program takes 1 argument. Ok let’s give it an argument ./vuln 1 Thanks! Received: 1 Lets try just throwing a bunch values at it ./vuln 11111111111111111111111111111111111 picoCTF{ov3rfl0ws_ar3nt_that_bad_3598a894} that was super simple but