HSCTF_2017: El Clasico

Category: Exploitation Points: 100 Description:

Since you’re reading this problem, you’re doing HSCTF, so we (the problem writers) think you’re cool. Keith, however, isn’t so easily convinced. Prove to Keith that you’re cool. Netcat to 104.131.90.29:8001. (Hint) Every CTF has one of these problems.

Write-up

A simple buffer overflow challenge. Be sure to take note of the address before RET.

Solution

$ ./solve.py 
[+] Opening connection to 104.131.90.29 on port 8001: Done
[*] Switching to interactive mode
$ git status
Cool people get a shell!
elclasico
elclasico.c
flag
run
fatal: Could not change back to '/root/problems': Permission denied
$ cat flag
one_of_these_pops_up_everytiem

Therefore, the flag is one_of_these_pops_up_everytiem.