pyLAPS.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# File name          : pyLAPS.py
# Author             : Podalirius (@podalirius_)
# Date created       : 05 Oct 2021

import argparse
import os
import sys
import ssl
import traceback
import random
import ldap3
from binascii import unhexlify
from impacket.smbconnection import SMBConnection
from impacket.spnego import SPNEGO_NegTokenInit, TypesMech
from ldap3.utils.conv import escape_filter_chars
from ldap3.protocol.formatters.formatters import format_sid


def get_machine_name(args, domain):
    if args.dc_ip is not None:
        s = SMBConnection(args.dc_ip, args.dc_ip)
    else:
        s = SMBConnection(domain, domain)
    try:
        s.login('', '')
    except Exception:
        if s.getServerName() == '':
            raise Exception('Error while anonymous logging into %s' % domain)
    else:
        s.logoff()
    return s.getServerName()


def init_ldap_connection(target, tls_version, args, domain, username, password, lmhash, nthash):
    user = '%s\\%s' % (domain, username)
    if tls_version is not None:
        use_ssl = True
        port = 636
        tls = ldap3.Tls(validate=ssl.CERT_NONE, version=tls_version)
    else:
        use_ssl = False
        port = 389
        tls = None
    ldap_server = ldap3.Server(target, get_info=ldap3.ALL, port=port, use_ssl=use_ssl, tls=tls)
    if args.use_kerberos:
        ldap_session = ldap3.Connection(ldap_server)
        ldap_session.bind()
        ldap3_kerberos_login(ldap_session, target, username, password, domain, lmhash, nthash, args.auth_key, kdcHost=args.dc_ip)
    elif args.auth_hashes is not None:
        if lmhash == "":
            lmhash = "aad3b435b51404eeaad3b435b51404ee"
        ldap_session = ldap3.Connection(ldap_server, user=user, password=lmhash + ":" + nthash, authentication=ldap3.NTLM, auto_bind=True)
    else:
        ldap_session = ldap3.Connection(ldap_server, user=user, password=password, authentication=ldap3.NTLM, auto_bind=True)

    return ldap_server, ldap_session


def init_ldap_session(args, domain, username, password, lmhash, nthash):
    if args.use_kerberos:
        target = get_machine_name(args, domain)
    else:
        if args.dc_ip is not None:
            target = args.dc_ip
        else:
            target = domain

    if args.use_ldaps is True:
        try:
            return init_ldap_connection(target, ssl.PROTOCOL_TLSv1_2, args, domain, username, password, lmhash, nthash)
        except ldap3.core.exceptions.LDAPSocketOpenError:
            return init_ldap_connection(target, ssl.PROTOCOL_TLSv1, args, domain, username, password, lmhash, nthash)
    else:
        return init_ldap_connection(target, None, args, domain, username, password, lmhash, nthash)


def ldap3_kerberos_login(connection, target, user, password, domain='', lmhash='', nthash='', aesKey='', kdcHost=None, TGT=None, TGS=None, useCache=True):
    from pyasn1.codec.ber import encoder, decoder
    from pyasn1.type.univ import noValue
    """
    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: True, raises an Exception if error.
    """

    if lmhash != '' or nthash != '':
        if len(lmhash) % 2:
            lmhash = '0' + lmhash
        if len(nthash) % 2:
            nthash = '0' + nthash
        try:  # just in case they were converted already
            lmhash = unhexlify(lmhash)
            nthash = unhexlify(nthash)
        except TypeError:
            pass

    # Importing down here so pyasn1 is not required if kerberos is not used.
    from impacket.krb5.ccache import CCache
    from impacket.krb5.asn1 import AP_REQ, Authenticator, TGS_REP, seq_set
    from impacket.krb5.kerberosv5 import getKerberosTGT, getKerberosTGS
    from impacket.krb5 import constants
    from impacket.krb5.types import Principal, KerberosTime, Ticket
    import datetime

    if TGT is not None or TGS is not None:
        useCache = False

    if useCache:
        try:
            ccache = CCache.loadFile(os.getenv('KRB5CCNAME'))
        except Exception as e:
            # No cache present
            print(e)
            pass
        else:
            # retrieve domain information from CCache file if needed
            if domain == '':
                domain = ccache.principal.realm['data'].decode('utf-8')
                print('[+] Domain retrieved from CCache: %s' % domain)

            print('[+] Using Kerberos Cache: %s' % os.getenv('KRB5CCNAME'))
            principal = 'ldap/%s@%s' % (target.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()
                    print('[+] Using TGT from cache')
                else:
                    print('[+] No valid credentials found in cache')
            else:
                TGS = creds.toTGS(principal)
                print('[+] 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')
                print('[+] Username retrieved from CCache: %s' % user)
            elif user == '' and len(ccache.principal.components) > 0:
                user = ccache.principal.components[0]['data'].decode('utf-8')
                print('[+] Username retrieved from CCache: %s' % user)

    # First of all, we need to get a TGT for the user
    userName = Principal(user, type=constants.PrincipalNameType.NT_PRINCIPAL.value)
    if TGT is None:
        if TGS is None:
            tgt, cipher, oldSessionKey, sessionKey = getKerberosTGT(userName, password, domain, lmhash, nthash, aesKey, kdcHost)
    else:
        tgt = TGT['KDC_REP']
        cipher = TGT['cipher']
        sessionKey = TGT['sessionKey']

    if TGS is None:
        serverName = Principal('ldap/%s' % target, type=constants.PrincipalNameType.NT_SRV_INST.value)
        tgs, cipher, oldSessionKey, sessionKey = getKerberosTGS(serverName, domain, kdcHost, tgt, cipher, sessionKey)
    else:
        tgs = TGS['KDC_REP']
        cipher = TGS['cipher']
        sessionKey = TGS['sessionKey']

        # 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 = []
    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)

    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'] = encoder.encode(apReq)

    request = ldap3.operation.bind.bind_operation(connection.version, ldap3.SASL, user, None, 'GSS-SPNEGO',
                                                  blob.getData())

    # Done with the Kerberos saga, now let's get into LDAP
    if connection.closed:  # try to open connection if closed
        connection.open(read_server_info=False)

    connection.sasl_in_progress = True
    response = connection.post_send_single_response(connection.send('bindRequest', request, None))
    connection.sasl_in_progress = False
    if response[0]['result'] != 0:
        raise Exception(response)

    connection.bound = True

    return True


class LAPSio(object):
    def __init__(self, ldap_server, ldap_session, domain):
        super(LAPSio, self).__init__()
        self.ldap_server = ldap_server
        self.ldap_session = ldap_session
        self.domain = domain

    def set(self, sAMAccountName, value):
        print("[+] Setting LAPS password in LDAP ... ")

        print("[+] Searching for the target computer")
        self.ldap_session.search(
            self.ldap_server.info.other["defaultNamingContext"],
            '(sAMAccountName=%s)' % escape_filter_chars(sAMAccountName),
            attributes=['objectSid']
        )
        dn, sid = None, None
        try:
            dn = self.ldap_session.entries[0].entry_dn
            sid = format_sid(self.ldap_session.entries[0]['objectSid'].raw_values[0])
        except IndexError:
            print("[!] Computer not found in LDAP: %s" % sAMAccountName)

        if dn is None and sid is None:
            print("[!] Target computer does not exist! (wrong domain?)")
        else:
            print("[+] Target computer found: %s" % dn)

        results = list(ldap_session.extend.standard.paged_search(
            dn,
            '(&(objectCategory=computer)(objectClass=*))',
            attributes=['sAMAccountName', 'objectSid', 'ms-Mcs-AdmPwd']
        ))
        for entry in results:
            if entry['type'] != 'searchResEntry':
                continue
            results = entry
        if len(results) == 0:
            print("[!] Could not query target computer properties.")
            return

        if value == None:
            alphabet = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
            value = ''.join([random.choice(list(alphabet)) for k in range(20)])
            print("[+] Using random password: %s" % value)

        self.ldap_session.modify(dn, {'ms-Mcs-AdmPwd': [ldap3.MODIFY_REPLACE, [bytes(value, "utf-8")]]})
        if self.ldap_session.result['result'] == 0:
            print("[+] Successfully updated the ms-Mcs-AdmPwd attribute of the target %s to %s" % (sAMAccountName, value))
        else:
            pass

    def get(self, sAMAccountName='*'):
        if sAMAccountName != '*' and sAMAccountName is not None:
            print("[+] Extracting LAPS password of computer: %s ..." % sAMAccountName)
            print("[+] Searching for the target computer: %s " % sAMAccountName)
            responses = list(ldap_session.extend.standard.paged_search(
                self.ldap_server.info.other["defaultNamingContext"],
                '(sAMAccountName=%s)' % escape_filter_chars(sAMAccountName),
                attributes=['objectSid']
            ))
            dn, sid = None, None
            try:
                dn = responses[0].entry_dn
                sid = format_sid(responses[0]['objectSid'].raw_values[0])
            except IndexError:
                print("[!] Computer not found in LDAP: %s" % sAMAccountName)

            if dn is None and sid is None:
                print("[!] Target computer does not exist! (wrong domain?)")
            else:
                print("[+] Target computer found: %s" % dn)

            responses = list(ldap_session.extend.standard.paged_search(
                dn,
                '(&(objectCategory=computer)(ms-MCS-AdmPwd=*)(sAMAccountName=%s))' % escape_filter_chars(sAMAccountName),
                attributes=['sAMAccountName', 'objectSid', 'ms-Mcs-AdmPwd']
            ))
        else:
            print("[+] Extracting LAPS passwords of all computers ... ")
            responses = list(ldap_session.extend.standard.paged_search(
                self.ldap_server.info.other["defaultNamingContext"],
                '(&(objectCategory=computer)(ms-MCS-AdmPwd=*)(sAMAccountName=*))',
                attributes=['sAMAccountName', 'objectSid', 'ms-Mcs-AdmPwd']
            ))

        results = []
        for entry in responses:
            if entry['type'] != 'searchResEntry':
                continue
            entry = entry["raw_attributes"]
            results.append(entry)
        return results


def parse_args():
    parser = argparse.ArgumentParser(add_help=True, description='Python setter/getter for property ms-Mcs-AdmPwd used by LAPS.')
    parser.add_argument('--use-ldaps', action='store_true', help='Use LDAPS instead of LDAP')
    parser.add_argument("-q", "--quiet", dest="quiet", action="store_true", default=False, help="show no information at all")
    parser.add_argument("-debug", dest="debug", action="store_true", default=False, help="Debug mode")
    parser.add_argument("-a", "--action", choices=['get', 'set'], nargs='?', default='get', help='Get or Set the LAPS password')
    parser.add_argument("-c", "--computer", type=str, default=None, required=False, dest="target_computer", help="Target computer to modify")
    parser.add_argument("-v", "--value", type=str, default=None, required=False, dest="target_value", help="New password to set")

    authconn = parser.add_argument_group('authentication & connection')
    authconn.add_argument('--dc-ip', action='store', metavar="ip address", help='IP Address of the domain controller or KDC (Key Distribution Center) for Kerberos. If omitted it will use the domain part (FQDN) specified in the identity parameter')
    authconn.add_argument("-d", "--domain", dest="auth_domain", metavar="DOMAIN", action="store", help="(FQDN) domain to authenticate to")
    authconn.add_argument("-u", "--user", dest="auth_username", metavar="USER", action="store", help="User to authenticate as")

    secret = parser.add_argument_group()
    cred = secret.add_mutually_exclusive_group()
    cred.add_argument('--no-pass', action="store_true", help='don\'t ask for password (useful for -k)')
    cred.add_argument("-p", "--password", dest="auth_password", metavar="PASSWORD", action="store", help="password to authenticate with")
    cred.add_argument("-H", "--hashes", dest="auth_hashes", action="store", metavar="[LMHASH:]NTHASH", help='NT/LM hashes, format is LMhash:NThash')
    cred.add_argument('--aes-key', dest="auth_key", action="store", metavar="hex key", help='AES key to use for Kerberos Authentication (128 or 256 bits)')
    secret.add_argument("-k", "--kerberos", dest="use_kerberos", action="store_true", help='Use Kerberos authentication. Grabs credentials from .ccache file (KRB5CCNAME) based on target parameters. If valid credentials cannot be found, it will use the ones specified in the command line')

    if len(sys.argv) == 1:
        parser.print_help()
        sys.exit(1)

    args = parser.parse_args()

    if args.action == "set" and args.target_computer is None:
        parser.error("The following arguments are required when setting -action == get: -c/--computer")

    return args


if __name__ == '__main__':
    print(r"""                 __    ___    ____  _____
    ____  __  __/ /   /   |  / __ \/ ___/
   / __ \/ / / / /   / /| | / /_/ /\__ \   
  / /_/ / /_/ / /___/ ___ |/ ____/___/ /   
 / .___/\__, /_____/_/  |_/_/    /____/    v1.2
/_/    /____/           @podalirius_           
    """)

    args = parse_args()

    auth_lm_hash = ""
    auth_nt_hash = ""
    if args.auth_hashes is not None:
        if ":" in args.auth_hashes:
            auth_lm_hash = args.auth_hashes.split(":")[0]
            auth_nt_hash = args.auth_hashes.split(":")[1]
        else:
            auth_nt_hash = args.auth_hashes

    try:
        ldap_server, ldap_session = init_ldap_session(
            args=args,
            domain=args.auth_domain,
            username=args.auth_username,
            password=args.auth_password,
            lmhash=auth_lm_hash,
            nthash=auth_nt_hash
        )

        _LAPSio = LAPSio(ldap_server, ldap_session, args.auth_domain)
        if args.action == 'set':
            _LAPSio.set(args.target_computer, args.target_value)
        elif args.action == 'get':
            results = _LAPSio.get(sAMAccountName=args.target_computer)
            results = sorted(results, key=lambda x:x["sAMAccountName"][0].decode('UTF-8'))
            for r in results:
                print("  | %-20s : %s" % (r["sAMAccountName"][0].decode('UTF-8'), r["ms-Mcs-AdmPwd"][0].decode('UTF-8')))
        print("[+] All done!")
    except Exception as e:
        if args.debug:
            traceback.print_exc()
        print("[!]", str(e))