Module: Msf::Exploit::Remote::RDP

Includes:
Tcp
Defined in:
lib/msf/core/exploit/remote/rdp.rb

Overview

This module exposes methods for interacting with a remote RDP service

Defined Under Namespace

Classes: RDPConstants, RdpCommunicationError

Instance Attribute Summary collapse

Attributes included from Tcp

#sock

Instance Method Summary collapse

Methods included from Tcp

#chost, #cleanup, #connect, #connect_timeout, #cport, #disconnect, #handler, #lhost, #lport, #peer, #print_prefix, #proxies, #rhost, #rport, #set_tcp_evasions, #shutdown, #ssl, #ssl_cipher, #ssl_verify_mode, #ssl_version

Instance Attribute Details

#rdp_sockObject (protected)

Returns the value of attribute rdp_sock.



1481
1482
1483
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1481

def rdp_sock
  @rdp_sock
end

#rdp_user_idObject (protected)

Returns the value of attribute rdp_user_id.



1483
1484
1485
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1483

def rdp_user_id
  @rdp_user_id
end

Instance Method Details

#ber_data(*ds) ⇒ Object (protected)



1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1372

def ber_data(*ds)
  data = ds.join('')

  result = [
    "\x82",
    [data.length].pack('S>'),
    data
  ].join('')

  result
end

#ber_int(i) ⇒ Object (protected)



1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1384

def ber_int(i)
  d = ''
  if i < (2 ** 8)
    d = [i].pack('C')
  elsif i < (2 ** 16)
    d = [i].pack('S>')
  else
    d = [i].pack('L>')
  end

  "\x02" + [d.length].pack('C') + d
end

#ber_octet_string(*ds) ⇒ Object (protected)



1363
1364
1365
1366
1367
1368
1369
1370
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1363

def ber_octet_string(*ds)
  result = [
    "\x04",
    ber_data(ds)
  ].join('')

  result
end

#bin_to_hex(str_val) ⇒ Object



697
698
699
# File 'lib/msf/core/exploit/remote/rdp.rb', line 697

def bin_to_hex(str_val)
  str_val.each_byte.map { |b| b.to_s(16).rjust(2, '0') }.join
end

#build_data_tpdu(data) ⇒ Object

Builds x.224 Data (DT) TPDU - Section 13.7



755
756
757
758
759
760
761
762
# File 'lib/msf/core/exploit/remote/rdp.rb', line 755

def build_data_tpdu(data)
  tpkt_length = data.length + 7

  "\x03\x00" +                 # TPKT Header version 03, reserved 0
    [tpkt_length].pack("S>") + # TPKT length
    "\x02\xf0\x80" +           # X.224 Data TPDU (2 bytes: 0xf0 = Data TPDU, 0x80 = EOT, end of transmission)
    data
end

#build_share_control_header(type, data) ⇒ Object



991
992
993
994
995
996
997
998
# File 'lib/msf/core/exploit/remote/rdp.rb', line 991

def build_share_control_header(type, data)
  total_len = data.length + 6

  [total_len].pack("S<") + # totalLength - includes all headers
    [type].pack("S<") +    # pduType - flags 16 bit, unsigned
    "\xf1\x03" +           # PDUSource: 0x03f1 = 1009
    data
end

#build_share_data_header(type, data) ⇒ Object



1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1002

def build_share_data_header(type, data)
  uncompressed_len = data.length + 4

  "\xea\x03\x01\x00" + # shareId: 66538
    "\x00" +     # pad1
    "\x01" +     # streamID: 1
    [uncompressed_len].pack("S<") + # uncompressedLength - 16 bit, unsigned int
    [type].pack("C") + # pduType2 - 8 bit, unsigned int - 2.2.8.1.1.2
    "\x00" +     # compressedType: 0
    "\x00\x00" + # compressedLength: 0
    data
end

#build_virtual_channel_pdu(flags, data) ⇒ Object



746
747
748
749
750
751
752
# File 'lib/msf/core/exploit/remote/rdp.rb', line 746

def build_virtual_channel_pdu(flags, data)
  data_len = data.length

  [data_len].pack("L<") + # length
    [flags].pack("L<") +  # flags
    data
end

#bytes_to_bignum(bytes_val, order = "little") ⇒ Object



672
673
674
675
676
677
678
679
# File 'lib/msf/core/exploit/remote/rdp.rb', line 672

def bytes_to_bignum(bytes_val, order = "little")
  bytes = bin_to_hex(bytes_val)
  if order == "little"
    bytes = bytes.scan(/../).reverse.join('')
  end
  s = "0x" + bytes
  s.to_i(16)
end

#conf_create_req(user_data_sets: 1, h221_key: "Duca") ⇒ Object (protected)



1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1340

def conf_create_req(user_data_sets: 1, h221_key: "Duca")
  b2 = 0
  b2 |= 0x08 if user_data_sets > 0

  b5 = 0x40
  b5 |= 0x80 if user_data_sets > 0

  # TODO: add more flags here
  [
    "\x00",
    [b2].pack('C'),
    "\x00\x10\x00",
    [user_data_sets].pack('C'),
    [b5].pack('C'),
    "\x00",
    [h221_key.encode('ASCII')].pack('a*')
  ].join('')
end

#cs_cluster_data(flags: RDPConstants::REDIRECTION_SUPPORTED | RDPConstants::REDIRECTION_VERSION3, session_id: 0) ⇒ Object (protected)



1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1246

def cs_cluster_data(
  flags: RDPConstants::REDIRECTION_SUPPORTED | RDPConstants::REDIRECTION_VERSION3,
  session_id: 0
)
  body = [flags, session_id].pack('<L<L')

  result = [
    [0xc004, body.length + 4].pack('<S<S'),
    body
  ].join('')

  result
end

#cs_core_data(version: 0x80004, width: 800, height: 600, keyboard: 1033, client_build: 2600, client_name: "rdesktop", keyboard_type: 4, keyboard_subtype: 0, keyboard_func_key: 12, serial_num: 0, client_product_id: 1, client_dig_product_id: "", selected_proto: 0) ⇒ Object (protected)



1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1292

def cs_core_data(
  version: 0x80004,
  width: 800,
  height: 600,
  keyboard: 1033, # English
  client_build: 2600,
  client_name: "rdesktop",
  keyboard_type: 4, # IBMEhanced 101/102
  keyboard_subtype: 0,
  keyboard_func_key: 12,
  serial_num: 0,
  client_product_id: 1,
  client_dig_product_id: "",
  selected_proto: 0
  )

  client_name = Rex::Text.to_unicode(client_name[0..16], 'utf-16le')
  client_dig_product_id = Rex::Text.to_unicode(client_dig_product_id[0..32], 'utf-16le')

  body = [
    [version, width, height].pack('<L<S<S'),
    "\x01\xca", # colour depth (8BPP)
    "\x03\xaa", # SASSequence
    [keyboard, client_build, client_name, keyboard_type].pack('<L<La32*'),
    [keyboard_type, keyboard_subtype, keyboard_func_key].pack('<L<L<L'),
    "\x00" * 64, # imeFileName
    "\x01\xca", # postBeta2ColorDepth (8BPP)
    [client_product_id, serial_num].pack('<S<L'),
    "\x18\x00", # highColorDepth: 24 bpp
    "\x07\x00", # supportedColorDepths: flag (24 bpp | 16 bpp | 15 bpp )
    "\x01\x00", # earlyCapabilityFlags: 1 (RNS_UD_CS_SUPPORT_ERRINFO_PDU)
    [client_dig_product_id].pack('a64*'),
    "\x00", # connectionType: 0
    "\x00", # pad1octet
    # serverSelectedProtocol - After negotiating TLS or CredSSP this value must
    # match the selectedProtocol value from the server's Negotiate Connection
    # confirm PDU that was sent before encryption was started.
    [selected_proto].pack('L<')
  ].join('')

  result = [
    [0xc001, body.length + 4].pack('<S<S'),
    body
  ].join('')

  result
end

#cs_network_data(channels) ⇒ Object (protected)



1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1274

def cs_network_data(channels)
  chan_data = channels.map{ |c|
    [c[0].encode('ASCII')].pack('a8*') + [c[1]].pack('L')
  }.join('')

  body = [
    [channels.length].pack('L'),
    chan_data
  ].join('')

  result = [
    [0xc003, body.length + 4].pack('<S<S'),
    body
  ].join('')

  result
end

#cs_security_data(encryption_methods: RDPConstants::ENCRYPTION_40BIT | RDPConstants::ENCRYPTION_128BIT, ext_encryption_methods: 0) ⇒ Object (protected)



1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1260

def cs_security_data(
  encryption_methods: RDPConstants::ENCRYPTION_40BIT | RDPConstants::ENCRYPTION_128BIT,
  ext_encryption_methods: 0
)
  body = [encryption_methods, ext_encryption_methods].pack('<L<L')

  result = [
    [0xc002, body.length + 4].pack('<S<S'),
    body
  ].join('')

  result
end

#encode_domain_selector(max_chan_ids: 0, max_user_ids: 0, max_token_ids: 0, num_priorities: 1, min_throughput: 0, max_height: 1, max_mcspdu_size: 65535, protocol_ver: 2) ⇒ Object (protected)



1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1191

def encode_domain_selector(
  max_chan_ids: 0,
  max_user_ids: 0,
  max_token_ids: 0,
  num_priorities: 1,
  min_throughput: 0,
  max_height: 1,
  max_mcspdu_size: 65535,
  protocol_ver: 2
)

  body = [
    ber_int(max_chan_ids),
    ber_int(max_user_ids),
    ber_int(max_token_ids),
    ber_int(num_priorities),
    ber_int(min_throughput),
    ber_int(max_height),
    ber_int(max_mcspdu_size),
    ber_int(protocol_ver)
  ].join('')

  result = [
    "\x30",
    [body.length].pack('C'),
    body
  ].join('')

  result
end

#initialize(info = {}) ⇒ Object

Creates an instance of a RDP exploit module.



17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
# File 'lib/msf/core/exploit/remote/rdp.rb', line 17

def initialize(info = {})
  super
  register_options(
    [
      OptString.new('RDP_USER', [ false, 'The username to report during connect, UNSET = random']),
      OptString.new('RDP_CLIENT_NAME', [ false, 'The client computer name to report during connect, UNSET = random', 'rdesktop']),
      OptString.new('RDP_DOMAIN', [ false, 'The client domain name to report during connect']),
      OptAddress.new('RDP_CLIENT_IP', [ true, 'The client IPv4 address to report during connect', '192.168.0.100']),
      Opt::RPORT(3389)
    ], Msf::Exploit::Remote::RDP)
    register_advanced_options(
    [
      OptInt.new('RDP_TLS_SECURITY_LEVEL', [ true, 'Change default TLS security level. "0" (default) means everything is permitted. "1" rejects very weak parameters and "2" is even stricter.', 0 ])
    ], Msf::Exploit::Remote::RDP)
end

#int_to_bytestring(int_val, num_chars = nil) ⇒ Object



682
683
684
685
686
687
688
689
690
691
692
693
694
695
# File 'lib/msf/core/exploit/remote/rdp.rb', line 682

def int_to_bytestring( int_val, num_chars = nil )
  unless num_chars
    bits_needed = Math.log(int_val) / Math.log(2)
    num_chars = ( bits_needed / 8.0 ).ceil
  end
  if pack_code = { 1 => 'C', 2 => 'S', 4 => 'L' }[num_chars]
    [int_val].pack(pack_code)
  else
    a = (0..(num_chars)).map{ |i|
      (( int_val >> i*8 ) & 0xFF ).chr
    }.join
    a[0..-2] # seems legit lol
  end
end

#oid(itut, rec, t, t124, ver, desc) ⇒ Object (protected)



1359
1360
1361
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1359

def oid(itut, rec, t, t124, ver, desc)
  [(itut << 8) | rec, t, t124, ver, desc].pack('C*')
end

#pdu_attach_user_requestObject



873
874
875
876
877
# File 'lib/msf/core/exploit/remote/rdp.rb', line 873

def pdu_attach_user_request
  pdu = "\x28"  # T.125 AttachUserRequest

  build_data_tpdu(pdu)
end

#pdu_channel_join_request(user1, channel_id) ⇒ Object



881
882
883
884
885
886
887
# File 'lib/msf/core/exploit/remote/rdp.rb', line 881

def pdu_channel_join_request(user1, channel_id)
  pdu =
    "\x38" + # T.125 ChannelJoinRequest
    [user1, channel_id].pack("nn")

  build_data_tpdu(pdu)
end

#pdu_client_confirm_activeObject



1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1077

def pdu_client_confirm_active
  pdu =
    "\xea\x03\x01\x00" + # shareId: 66538
    "\xea\x03" + # originatorId
    "\x06\x00" + # lengthSourceDescriptor: 6
    "\x8e\x01" + # lengthCombinedCapabilities: 398
    "\x4d\x53\x54\x53\x43\x00" + # SourceDescriptor: 'MSTSC'
    "\x0e\x00" + # numberCapabilities: 14
    "\x00\x00" + # pad2Octets
    "\x01\x00" + # capabilitySetType: 1 - TS_GENERAL_CAPABILITYSET
    "\x18\x00" + # lengthCapability: 24
    "\x01\x00\x03\x00\x00\x02\x00\x00\x00\x00\x0d\x04\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00" + #
    "\x02\x00" + # capabilitySetType: 2 - TS_BITMAP_CAPABILITYSET
    "\x1c\x00" + # lengthCapability: 28
    "\x10\x00\x01\x00\x01\x00\x01\x00\x20\x03\x58\x02\x00\x00\x01\x00" + #
    "\x01\x00\x00\x00\x01\x00\x00\x00" + #
    "\x03\x00" + # capabilitySetType: 3 - TS_ORDER_CAPABILITYSET
    "\x58\x00" + # lengthCapability: 88
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x01\x00\x14\x00\x00\x00\x01\x00\x47\x01\x2a\x00" + #
    "\x01\x01\x01\x01\x00\x00\x00\x00\x01\x01\x01\x01\x00\x01\x01\x00" + #
    "\x00\x00\x00\x00\x01\x01\x01\x00\x00\x01\x01\x01\x00\x00\x00\x00" + #
    "\xa1\x06\x00\x00\x00\x00\x00\x00\x00\x84\x03\x00\x00\x00\x00\x00" + #
    "\xe4\x04\x00\x00\x13\x00\x28\x00\x00\x00\x00\x03\x78\x00\x00\x00" + #
    "\x78\x00\x00\x00\x50\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x08\x00" + # capabilitySetType: 8 - TS_POINTER_CAPABILITYSET
    "\x0a\x00" + # lengthCapability: 10
    "\x01\x00\x14\x00\x14\x00" + #
    "\x0a\x00" + # capabilitySetType: 10 - TS_COLORTABLE_CAPABILITYSET
    "\x08\x00" + # lengthCapability: 8
    "\x06\x00\x00\x00" + #
    "\x07\x00" + # capabilitySetType: 7 - TSWINDOWACTIVATION_CAPABILITYSET
    "\x0c\x00" + # lengthCapability: 12
    "\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x05\x00" + # capabilitySetType: 5 - TS_CONTROL_CAPABILITYSET
    "\x0c\x00" + # lengthCapability: 12
    "\x00\x00\x00\x00\x02\x00\x02\x00" + #
    "\x09\x00" + # capabilitySetType: 9 - TS_SHARE_CAPABILITYSET
    "\x08\x00" + # lengthCapability: 8
    "\x00\x00\x00\x00" + #
    "\x0f\x00" + # capabilitySetType: 15 - TS_BRUSH_CAPABILITYSET
    "\x08\x00" + # lengthCapability: 8
    "\x01\x00\x00\x00" + #
    "\x0d\x00" + # capabilitySetType: 13 - TS_INPUT_CAPABILITYSET
    "\x58\x00" + # lengthCapability: 88
    "\x01\x00\x00\x00\x09\x04\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00" + #
    "\x0c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00" + #
    "\x0c\x00" + # capabilitySetType: 12 - TS_SOUND_CAPABILITYSET
    "\x08\x00" + # lengthCapability: 8
    "\x01\x00\x00\x00" + #
    "\x0e\x00" + # capabilitySetType: 14 - TS_FONT_CAPABILITYSET
    "\x08\x00" + # lengthCapability: 8
    "\x01\x00\x00\x00" + #
    "\x10\x00" + # capabilitySetType: 16 - TS_GLYPHCAChE_CAPABILITYSET
    "\x34\x00" + # lengthCapability: 52
    "\xfe\x00\x04\x00\xfe\x00\x04\x00\xfe\x00\x08\x00\xfe\x00\x08\x00" + #
    "\xfe\x00\x10\x00\xfe\x00\x20\x00\xfe\x00\x40\x00\xfe\x00\x80\x00" + #
    "\xfe\x00\x00\x01\x40\x00\x00\x08\x00\x01\x00\x01\x02\x00\x00\x00"

  # type = 0x13 = TS_PROTOCOL_VERSION | PDUTYPE_CONFIRMACTIVEPDU
  build_share_control_header(0x13, pdu)
end

#pdu_client_control_cooperateObject



1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1017

def pdu_client_control_cooperate
  pdu =
    "\x04\x00" +       # action: 4 - CTRLACTION_COOPERATE
    "\x00\x00" +       # grantId: 0
    "\x00\x00\x00\x00" # controlId: 0

  # pduType2 = 0x14 = 20 - PDUTYPE2_CONTROL
  data_header = build_share_data_header(0x14, pdu)

  # type = 0x17 = TS_PROTOCOL_VERSION | PDUTYPE_DATAPDU
  build_share_control_header(0x17, data_header)
end

#pdu_client_control_requestObject



1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1032

def pdu_client_control_request
  pdu =
    "\x01\x00" +       # action: 1 - CTRLACTION_REQUEST_CONTROL
    "\x00\x00" +       # grantId: 0
    "\x00\x00\x00\x00" # controlId: 0

  # pduType2 = 0x14 = 20 - PDUTYPE2_CONTROL
  data_header = build_share_data_header(0x14, pdu)

  # type = 0x17 = TS_PROTOCOL_VERSION | PDUTYPE_DATAPDU
  build_share_control_header(0x17, data_header)
end

#pdu_client_font_listObject



1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1047

def pdu_client_font_list
  pdu =
    "\x00\x00" + # numberFonts: 0
    "\x00\x00" + # totalNumberFonts: 0
    "\x03\x00" + # listFlags: 3 (FONTLIST_FIRST | FONTLIST_LAST)
    "\x32\x00"   # entrySize: 50

  # pduType2 = 0x27 = 29 -  PDUTYPE2_FONTLIST
  data_header = build_share_data_header(0x27, pdu)

  # type = 0x17 = TS_PROTOCOL_VERSION | PDUTYPE_DATAPDU
  build_share_control_header(0x17, data_header)
end

#pdu_client_info(user_name, domain_name = "", ip_address = "") ⇒ Object



921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
# File 'lib/msf/core/exploit/remote/rdp.rb', line 921

def pdu_client_info(user_name, domain_name = "", ip_address = "")
  # Max len for 4.0/6.0 servers is 44 bytes including terminator
  # Max len for all other versions is 512 including terminator
  # We're going to limit to 44 (21 chars + null -> unicode) here.
  # Blank username is ok, nil = random
  user_name = Rex::Text.rand_text_alpha(10) if user_name.nil?
  user_unicode = Rex::Text.to_unicode(user_name[0..20], 'utf-16le')
  uname_len = user_unicode.length

  # Domain can can be, and for rdesktop typically is, empty.
  # Max len for 4.0/5.0 servers is 52 including terminator
  # Max len for all other versions is 512 including terminator
  # We're going to limit to 52 (25 chars + null -> unicode) here.
  domain_unicode = Rex::Text.to_unicode(domain_name[0..24], 'utf-16le')
  domain_len = domain_unicode.length

  # This address value is primarily used to reduce the fields by which this
  # module can be fingerprinted. It doesn't show up in Windows logs.
  # clientAddress + null terminator
  ip_unicode = Rex::Text.to_unicode(ip_address, 'utf-16le') + "\x00\x00"
  ip_len = ip_unicode.length

  "\x00\x00\x00\x00" +    # CodePage
    "\x33\x01\x00\x00" +  # flags - INFO_MOUSE, INFO_DISABLECTRLALTDEL, INFO_UNICODE, INFO_MAXIMIZESHELL, INFO_ENABLEWINDOWSKEY
    [domain_len].pack("S<") + # cbDomain (length value) - EXCLUDES null terminator
    [uname_len].pack("S<") +  # cbUserName (length value) - EXCLUDES null terminator
    "\x00\x00" +  # cbPassword (length value)
    "\x00\x00" +  # cbAlternateShell (length value)
    "\x00\x00" +  # cbWorkingDir (length value)
    [domain_unicode].pack("a*") + # Domain
    "\x00\x00" +                  # Domain null terminator, EXCLUDED from value of cbDomain
    [user_unicode].pack("a*") +   # UserName
    "\x00\x00" +  # UserName null terminator, EXCLUDED FROM value of cbUserName
    "\x00\x00" +  # Password - empty
    "\x00\x00" +  # AlternateShell - empty
    "\x00\x00" +  # WorkingDir - empty
    # TS_EXTENDED_INFO_PACKET - 2.2.1.11.1.1.1
    "\x02\x00" +              # clientAddressFamily - AF_INET - FIXFIX - detect and set dynamically
    [ip_len].pack("S<") +     # cbClientAddress (length value) - INCLUDES terminator ... for reasons.
    [ip_unicode].pack("a*") + # clientAddress (unicode + null terminator (unicode)
    "\x3c\x00" +              # cbClientDir (length value): 60
    # clientDir - 'C:\WINNT\System32\mstscax.dll' + null terminator
    "\x3c\x00\x43\x00\x3a\x00\x5c\x00\x57\x00\x49\x00\x4e\x00\x4e\x00" + #
    "\x54\x00\x5c\x00\x53\x00\x79\x00\x73\x00\x74\x00\x65\x00\x6d\x00" + #
    "\x33\x00\x32\x00\x5c\x00\x6d\x00\x73\x00\x74\x00\x73\x00\x63\x00" + #
    "\x61\x00\x78\x00\x2e\x00\x64\x00\x6c\x00\x6c\x00\x00\x00" + #
    # clientTimeZone - TS_TIME_ZONE struct - 172 bytes
    # These are the default values for rdesktop
    "\xa4\x01\x00\x00" + # Bias
    # StandardName - 'GTB,normaltid'
    "\x47\x00\x54\x00\x42\x00\x2c\x00\x20\x00\x6e\x00\x6f\x00\x72\x00" + #
    "\x6d\x00\x61\x00\x6c\x00\x74\x00\x69\x00\x64\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x0a\x00\x00\x00\x05\x00\x03\x00\x00\x00\x00\x00\x00\x00" + # StandardDate - Oct 5
    "\x00\x00\x00\x00" + # StandardBias
    # DaylightName - 'GTB,sommartid'
    "\x47\x00\x54\x00\x42\x00\x2c\x00\x20\x00\x73\x00\x6f\x00\x6d\x00" + #
    "\x6d\x00\x61\x00\x72\x00\x74\x00\x69\x00\x64\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" + #
    "\x00\x00\x03\x00\x00\x00\x05\x00\x02\x00\x00\x00\x00\x00\x00\x00" + # DaylightDate - Mar 3
    "\xc4\xff\xff\xff" + # DaylightBias
    "\x00\x00\x00\x00" + # clientSessionId
    "\x27\x00\x00\x00" + # performanceFlags
    "\x00\x00"           # cbAutoReconnectCookie
end

#pdu_client_input_event_sychronizeObject



1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1148

def pdu_client_input_event_sychronize
  pdu =
    "\x01\x00" +         # numEvents: 1
    "\x00\x00" +         # pad2Octets
    "\x00\x00\x00\x00" + # eventTime
    "\x00\x00" +         # messageType: 0 - INPUT_EVENT_SYNC
    # TS_SYNC_EVENT 202.8.1.1.3.1.1.5
    "\x00\x00" +         # pad2Octets
    "\x00\x00\x00\x00"   # toggleFlags

  # pduType2 = 0x1c = 28 - PDUTYPE2_INPUT
  data_header = build_share_data_header(0x1c, pdu)

  # type = 0x17 = TS_PROTOCOL_VERSION | PDUTYPE_DATAPDU
  build_share_control_header(0x17, data_header)
end

#pdu_client_synchronize(target_user = 0) ⇒ Object



1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1063

def pdu_client_synchronize(target_user = 0)
  pdu =
    "\x01\x00" +              # messageType: 1 SYNCMSGTYPE_SYNC
    [target_user].pack("S<")  # targetUser, 16 bit, unsigned.

  # pduType2 = 0x1f = 31 - PDUTYPE2_SCYNCHRONIZE
  data_header = build_share_data_header(0x1f, pdu)

  # type = 0x17 = TS_PROTOCOL_VERSION | PDUTYPE_DATAPDU
  build_share_control_header(0x17, data_header)
end

#pdu_connect_initial(channels, selected_proto = 0, host_name = "rdesktop") ⇒ Object



811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
# File 'lib/msf/core/exploit/remote/rdp.rb', line 811

def pdu_connect_initial(channels, selected_proto = 0, host_name = "rdesktop")
  # After negotiating TLS or NLA the connectInitial packet needs to include the
  # protocol selection that the server indicated in its Negotiation Response

  pdu = [
    "\x7f\x65",        # T.125 Connect-Initial (BER: Application 101)
    ber_data(
      "\x04\x01\x01",    # CallingDomainSelector: 1 (BER: OctetString)
      "\x04\x01\x01",    # CalledDomainSelector: 1 (BER: OctetString)
      "\x01\x01\xff",    # UpwaredFlag: True (BER: boolean)

      # TargetParamenters
      encode_domain_selector(
        max_chan_ids: 0x22,
        max_user_ids: 0x2
      ),
      # MinimumParameters
      encode_domain_selector(
        max_chan_ids: 0x1,
        max_user_ids: 0x1,
        max_token_ids: 0x1,
        max_mcspdu_size: 0x0420
      ),
      # MaximumParameters
      encode_domain_selector(
        max_chan_ids: 0xffff,
        max_user_ids: 0xfc17,
        max_token_ids: 0xffff
      ),
      # UserData
      ber_octet_string(
        # T.124 GCC Connection Data (ConnectData)- PER Encoding used
        per_object(oid(0, 0, 20, 124, 0, 1)),
        per_data(
          conf_create_req(),
          per_data(
            cs_core_data(client_name: host_name, selected_proto: selected_proto),
            cs_cluster_data(),
            cs_security_data(),
            cs_network_data(channels)
          )
        )
      )
    )
  ].join('')

  build_data_tpdu(pdu)
end

#pdu_erect_domain_requestObject



862
863
864
865
866
867
868
869
# File 'lib/msf/core/exploit/remote/rdp.rb', line 862

def pdu_erect_domain_request
  pdu =
    "\x04" +       # T.125 ErectDomainRequest
    "\x01\x00" +   # subHeight - length 1, value 0
    "\x01\x00"     # subInterval - length 1, value 0

  build_data_tpdu(pdu)
end

#pdu_negotiation_request(user_name = "", requested_protocols = 0) ⇒ Object



788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
# File 'lib/msf/core/exploit/remote/rdp.rb', line 788

def pdu_negotiation_request(user_name = "", requested_protocols = 0)
  # Blank username is ok, nil = random
  user_name = Rex::Text.rand_text_alpha(12) if user_name.nil?
  tpkt_len = user_name.length + 38
  x224_len = user_name.length + 33

  "\x03\x00" +              # TPKT Header version 03, reserved 0
    [tpkt_len].pack("S>") + # TPKT length: 43
    [x224_len].pack("C") +  # X.224 LengthIndicator
    "\xe0" +        # X.224 Type: Connect Request
    "\x00\x00" +    # dst reference
    "\x00\x00" +    # src reference
    "\x00" +        # class and options
    # cookie - literal 'Cookie: mstshash='
    "\x43\x6f\x6f\x6b\x69\x65\x3a\x20\x6d\x73\x74\x73\x68\x61\x73\x68\x3d" +
    user_name +     # Identifier "username"
    "\x0d\x0a" +    # cookie terminator
    "\x01\x00" +    # Type: RDP Negotiation Request ( 0x01 )
    "\x08\x00" +    # Length
    [requested_protocols].pack('L<') # requestedProtocols
end

#pdu_new_license_request(client_random, user, host) ⇒ Object



766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
# File 'lib/msf/core/exploit/remote/rdp.rb', line 766

def pdu_new_license_request(client_random, user, host)
  length = 24 + client_random.length + 64 + user.length + 1 + host.length + 1

  [RDPConstants::LICENSE_NEW_LICENSE_REQ].pack("C") +
  "\x03" +                         # Version
  [length].pack("S<") +            # Length
  "\x01\x01\x00\x00\x00\x01\xff" + # KEY_EXCHANGE_ALG_RSA
  client_random[0..31] +
  "\x02\x00" +                     # Encrypted Premaster Secret RANDOM_BLOB
  [64].pack("S<") +
  "\x00" * 64 +                    # The client license premaster secret, we don't care about the license contents
  "\x0f\x00" +                     # USER_NAME_BLOB
  [user.length + 1].pack("S<") +
  user + "\x00" +
  "\x10\x00" +                     # CLIENT_MACHINE_NAME_BLOB
  [host.length + 1].pack("S<") +
  host + "\x00"

end

#pdu_security_exchange(rcran, rsexp, rsmod, bitlen) ⇒ Object



891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
# File 'lib/msf/core/exploit/remote/rdp.rb', line 891

def pdu_security_exchange(rcran, rsexp, rsmod, bitlen)
  encrypted_rcran_bignum = rsa_encrypt(rcran, rsexp, rsmod)
  encrypted_rcran = int_to_bytestring(encrypted_rcran_bignum)

  bitlen += 8 # Pad with size of TS_SECURITY_PACKET header

  userdata_length = 8 + bitlen
  userdata_length_low = userdata_length & 0xFF
  userdata_length_high = userdata_length / 256
  flags = 0x80 | userdata_length_high

  pdu =
    "\x64" +            # T.125 sendDataRequest
    "\x00\x08" +        # intiator userId
    "\x03\xeb" +        # channelId = 1003
    "\x70" +            # dataPriority = high, segmentation = begin | end
    [flags].pack("C") +
    [userdata_length_low].pack("C") + # UserData length
    # TS_SECURITY_PACKET - 2.2.1.10.1
    "\x01\x00" +           # securityHeader flags
    "\x00\x00" +           # securityHeader flagsHi
    [bitlen].pack("L<") +  # TS_ length
    encrypted_rcran +      # encryptedClientRandom - 64 bytes
    "\x00\x00\x00\x00\x00\x00\x00\x00" # 8 bytes rear padding (always present)

  build_data_tpdu(pdu)
end

#per_data(*ds) ⇒ Object (protected)



1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1234

def per_data(*ds)
  data = ds.join('')
  result = ''
  if data.length < 0x4000
    result = [data.length | 0x8000].pack('S>') + data
  else
    result = "\xA2" + [data.length].pack('S>') + data
  end

  result
end

#per_object(*ds) ⇒ Object (protected)



1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1222

def per_object(*ds)
  body = ds.join('')

  result = [
    "\x00",
    [body.length].pack('C'),
    body
  ].join('')

  result
end

#rdp_build_pkt(data, channel_id = "\x03\xeb", client_info: false, license_info: false) ⇒ Object

Build the X.224 packet, encrypt with Standard RDP Security as needed default channel_id = 0x03eb = 1003



708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
# File 'lib/msf/core/exploit/remote/rdp.rb', line 708

def rdp_build_pkt(data, channel_id = "\x03\xeb", client_info: false, license_info: false)
  flags = 0
  flags |= 0x08 if @rdp_sec     # Set SEC_ENCRYPT
  flags |= 0x40 if client_info  # Set SEC_INFO_PKT
  flags |= 0x80 if license_info # Set SEC_LICENSE_PKT

  pdu = ""

  # TS_SECURITY_HEADER - 2.2.8.1.1.2.1
  # Send when the packet is encrypted w/ Standard RDP Security and in all Client Info PDUs
  if client_info || @rdp_sec
    pdu << [flags].pack("S<")  # flags  "\x48\x00" = SEC_INFO_PKT | SEC_ENCRYPT
    pdu << "\x00\x00"          # flagsHi
  end

  if @rdp_sec
    # Encrypt the payload with RDP Standard Encryption
    pdu << rdp_hmac(@hmackey, data)[0..7]
    pdu << rdp_rc4_crypt(@rc4enckey, data)
  else
    pdu << data
  end

  user_data_len = pdu.length
  udl_with_flag = 0x8000 | user_data_len

  pkt =  "\x64"      # sendDataRequest
  pkt << "\x00\x08"  # intiator userId .. TODO: for a functional client this isn't static
  pkt << channel_id  # channelId
  pkt << "\x70"      # dataPriority
  pkt << [udl_with_flag].pack("S>")
  pkt << pdu

  build_data_tpdu(pkt)
end

#rdp_calculate_rc4_keys(client_random, server_random) ⇒ Object



641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
# File 'lib/msf/core/exploit/remote/rdp.rb', line 641

def rdp_calculate_rc4_keys(client_random, server_random)
  # g = First192Bits(ClientRandom) + First192Bits(ServerRandom)
  g = client_random[0..23] + server_random[0..23]

  # PreMasterHash(I) = SaltedHash(g, I)
  # MasterSecret = PreMasterHash(0x41) + PreMasterHash(0x4242) + PreMasterHash(0x434343)
  master_secret = rdp_salted_hash48(g, "A", client_random, server_random)

  # MasterHash(I) = SaltedHash(MasterSecret, I)
  # SessionKeyBlob = MasterHash(0x58) + MasterHash(0x5959) + MasterHash(0x5A5A5A)
  sessionKeyBlob = rdp_salted_hash48(master_secret, "X", client_random, server_random)

  # InitialClientDecryptKey128 = FinalHash(Second128Bits(SessionKeyBlob))
  initialClientDecryptKey128 = rdp_final_hash(sessionKeyBlob[16..31], client_random, server_random)

  # InitialClientEncryptKey128 = FinalHash(Third128Bits(SessionKeyBlob))
  initialClientEncryptKey128 = rdp_final_hash(sessionKeyBlob[32..47], client_random, server_random)

  mac_key = sessionKeyBlob[0..15]

  return initialClientEncryptKey128, initialClientDecryptKey128, mac_key, sessionKeyBlob
end

#rdp_check_protocol(req_proto = RDPConstants::PROTOCOL_SSL) ⇒ Boolean, RDPConstants

Connect and detect security protocol

Note: NLA is detected but not supported yet

Returns:

  • (Boolean)

    Is service RDP

  • (RDPConstants)

    Protocol supported



259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
# File 'lib/msf/core/exploit/remote/rdp.rb', line 259

def rdp_check_protocol(req_proto = RDPConstants::PROTOCOL_SSL)
  if datastore['RDP_USER']
    @user_name = datastore['RDP_USER']
  else
    @user_name = Rex::Text.rand_text_alpha(7)
  end

  if datastore['RDP_DOMAIN']
    @domain = datastore['RDP_DOMAIN']
  else
    @domain = Rex::Text.rand_text_alpha(7)
  end

  if datastore['RDP_CLIENT_NAME']
    @computer_name = datastore['RDP_CLIENT_NAME']
  else
    @computer_name = Rex::Text.rand_text_alpha(15)
  end

  @ip_address = datastore['RDP_CLIENT_IP']

  # code to check if RDP is open or not
  vprint_status("Verifying RDP protocol...")

  vprint_status("Attempting to connect using TLS security")
  res = rdp_send_recv(pdu_negotiation_request(@user_name, req_proto))

  # return true if the response is a X.224 Connect Confirm
  # We can't use a check for RDP Negotiation Response because WinXP excludes it
  if res
    result, err_msg = rdp_parse_negotiation_response(res)
    return true, result if result

    # No current support for NLA, nothing to do here
    return true, RDPConstants::PROTOCOL_HYBRID if err_msg == 'HYBRID_REQUIRED_BY_SERVER'

    if err_msg == "Negotiation Response packet too short."
      vprint_status("Attempt to connect with TLS failed but looks like the target is Windows XP")
    else
      vprint_status("Attempt to connect with TLS failed with error: #{err_msg}")
    end

    if ["SSL_NOT_ALLOWED_BY_SERVER", "Negotiation Response packet too short."].include? err_msg
      # This happens if the server is configured to ONLY permit RDP Security
      vprint_status("Attempting to connect using Standard RDP security")
      rdp_disconnect
      rdp_connect
      res = rdp_send_recv(pdu_negotiation_request(@user_name, RDPConstants::PROTOCOL_RDP))

      if res
        result, err_msg = rdp_parse_negotiation_response(res)
        return true, result if result

        # Windows XP doesn't return the standard Negotiation Response packet
        # but we at least know this was RDP since the packet contained a
        # Connect-Confirm response (0xd0).
        if err_msg == "Negotiation Response packet too short."
          return true, RDPConstants::PROTOCOL_RDP
        end

        vprint_status("Attempt to connect with Standard RDP failed with error #{err_msg}")
      end
    end
  end

  return false, 0
end

#rdp_connectObject



143
144
145
146
# File 'lib/msf/core/exploit/remote/rdp.rb', line 143

def rdp_connect
  self.rdp_sock = connect(false)
  self.rdp_sock.setsockopt(::Socket::IPPROTO_TCP, ::Socket::TCP_NODELAY, 1)
end

#rdp_create_channel_msg(chan_user_id, chan_id, data, flags = 3, data_length = nil) ⇒ Object



225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
# File 'lib/msf/core/exploit/remote/rdp.rb', line 225

def rdp_create_channel_msg(chan_user_id, chan_id, data, flags = 3, data_length = nil)
  data_length ||= data.length

  pdu = [
    [25 << 2].pack('C'), # MCS send data request structure, choice 25
    [self.rdp_user_id, chan_id].pack('S>S>'), # MCS send data request structure, choice 25
    "\x70", # Wut (security header)
    per_data(
      [data_length].pack('<L'),
      [flags].pack('<L'),
      data
    )
  ].join('')

  build_data_tpdu(pdu)
end

#rdp_disconnectObject



148
149
150
151
# File 'lib/msf/core/exploit/remote/rdp.rb', line 148

def rdp_disconnect
  disconnect(self.rdp_sock)
  self.rdp_sock = nil
end

#rdp_dispatch_loopObject



219
220
221
222
223
# File 'lib/msf/core/exploit/remote/rdp.rb', line 219

def rdp_dispatch_loop
  while rdp_sock do
    rdp_handle_packet(rdp_recv)
  end
end

#rdp_establish_sessionObject

Finish building session after all security is negotiated



449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
# File 'lib/msf/core/exploit/remote/rdp.rb', line 449

def rdp_establish_session
  vprint_status("Sending client info PDU")
  res = rdp_send_recv(rdp_build_pkt(pdu_client_info(@user_name, @domain, @ip_address),
                                    "\x03\xeb", client_info: true))
  vprint_status("Received License packet (#{res.length} bytes)")
  rdp_parse_license_pdu(res)

  # Windows XP sometimes sends a very large license packet. This is likely
  # some form of license error. When it does this it doesn't send a Server
  # Demand packet. If we wait on one we will time out here and error. We
  # can still successfully check for vulnerability anyway.
  if res.length <= 34
    vprint_status("Waiting for Server Demand packet")
    _res = rdp_recv
    vprint_status("Received Server Demand packet")
  end

  vprint_status("Sending client confirm active PDU")
  rdp_send(rdp_build_pkt(pdu_client_confirm_active))

  vprint_status("Sending client synchronize PDU")
  vprint_status("Sending client control cooperate PDU")
  # Unsure why we're using 1009 here but it works.
  synch = rdp_build_pkt(pdu_client_synchronize(1009))
  coop = rdp_build_pkt(pdu_client_control_cooperate)
  rdp_send(synch + coop)

  vprint_status("Sending client control request control PDU")
  rdp_send(rdp_build_pkt(pdu_client_control_request))

  vprint_status("Sending client input sychronize PDU")
  rdp_send(rdp_build_pkt(pdu_client_input_event_sychronize))

  vprint_status("Sending client font list PDU")
  rdp_send(rdp_build_pkt(pdu_client_font_list))
end

#rdp_final_hash(k, client_random_bytes, server_random_bytes) ⇒ Object

FinalHash(K) = MD5(K + ClientRandom + ServerRandom)



631
632
633
634
635
636
637
638
639
# File 'lib/msf/core/exploit/remote/rdp.rb', line 631

def rdp_final_hash(k, client_random_bytes, server_random_bytes)
  md5 = Digest::MD5.new

  md5 << k
  md5 << client_random_bytes
  md5 << server_random_bytes

  [md5.hexdigest].pack("H*")
end

#rdp_fingerprintBoolean, Hash

Connect and perform fingerprinting of the RDP service

Note: NLA is required to detect the product_version

Returns:

  • (Boolean)

    Is service RDP

  • (Hash)

    Version information



177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
# File 'lib/msf/core/exploit/remote/rdp.rb', line 177

def rdp_fingerprint
  peer_info = {}
  # warning: if rdp_check_protocol starts handling NLA, this will need to be updated
  is_rdp, server_selected_proto = rdp_check_protocol(RDPConstants::PROTOCOL_SSL | RDPConstants::PROTOCOL_HYBRID | RDPConstants::PROTOCOL_HYBRID_EX)
  return false, nil unless is_rdp
  return true, peer_info unless [RDPConstants::PROTOCOL_HYBRID, RDPConstants::PROTOCOL_HYBRID_EX].include? server_selected_proto

  swap_sock_plain_to_ssl
  ntlm_negotiate_blob = ''  # see: https://fadedlab.wordpress.com/2019/06/13/using-nmap-to-extract-windows-info-from-rdp/
  ntlm_negotiate_blob << "\x30\x37\xa0\x03\x02\x01\x60\xa1\x30\x30\x2e\x30\x2c\xa0\x2a\x04\x28"
  ntlm_negotiate_blob << "\x4e\x54\x4c\x4d\x53\x53\x50\x00"  #  Identifier - NTLMSSP
  ntlm_negotiate_blob << "\x01\x00\x00\x00"                  #  Type: NTLMSSP Negotiate - 01
  ntlm_negotiate_blob << "\xb7\x82\x08\xe2"                  #  Flags (NEGOTIATE_SIGN_ALWAYS | NEGOTIATE_NTLM | NEGOTIATE_SIGN | REQUEST_TARGET | NEGOTIATE_UNICODE)
  ntlm_negotiate_blob << "\x00\x00"                          #  DomainNameLen
  ntlm_negotiate_blob << "\x00\x00"                          #  DomainNameMaxLen
  ntlm_negotiate_blob << "\x00\x00\x00\x00"                  #  DomainNameBufferOffset
  ntlm_negotiate_blob << "\x00\x00"                          #  WorkstationLen
  ntlm_negotiate_blob << "\x00\x00"                          #  WorkstationMaxLen
  ntlm_negotiate_blob << "\x00\x00\x00\x00"                  #  WorkstationBufferOffset
  ntlm_negotiate_blob << "\x0a"                              #  ProductMajorVersion = 10
  ntlm_negotiate_blob << "\x00"                              #  ProductMinorVersion = 0
  ntlm_negotiate_blob << "\x63\x45"                          #  ProductBuild = 0x4563 = 17763
  ntlm_negotiate_blob << "\x00\x00\x00"                      #  Reserved
  ntlm_negotiate_blob << "\x0f"                              #  NTLMRevision = 5 = NTLMSSP_REVISION_W2K3
  resp = rdp_send_recv(ntlm_negotiate_blob)

  ntlmssp_start = resp.index('NTLMSSP')
  if ntlmssp_start
    message = Net::NTLM::Message.parse(resp[ntlmssp_start..-1])
    version = message.os_version.bytes
    ti = Net::NTLM::TargetInfo.new(message.target_info)

    peer_info[:nb_name] = ti.av_pairs[Net::NTLM::TargetInfo::MSV_AV_NB_COMPUTER_NAME]
    peer_info[:nb_domain] = ti.av_pairs[Net::NTLM::TargetInfo::MSV_AV_NB_DOMAIN_NAME ]
    peer_info[:dns_server] = ti.av_pairs[Net::NTLM::TargetInfo::MSV_AV_DNS_COMPUTER_NAME]
    peer_info[:dns_domain] = ti.av_pairs[Net::NTLM::TargetInfo::MSV_AV_DNS_DOMAIN_NAME]
    peer_info[:product_version] = "#{version[0]}.#{version[1]}.#{version[2] | (version[3] << 8)}"
  end

  return is_rdp, peer_info
end

#rdp_generate_license_keys(data) ⇒ Object



378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
# File 'lib/msf/core/exploit/remote/rdp.rb', line 378

def rdp_generate_license_keys(data)
  client_random = ''
  32.times { client_random << rand(0..255) }
  premaster_secret = ''
  32.times { premaster_secret << rand(0..255) }
  server_random = data[0..31]

  master_secret = rdp_salted_hash48(premaster_secret, "A", client_random, server_random)
  key_block = rdp_salted_hash48(master_secret, "A", client_random, server_random)

  license_sign_key = key_block[0..15]
  license_key = rdp_salted_hash16(key_block[16..31], client_random, server_random)

  return client_random, license_key, license_sign_key
end

#rdp_handle_license_error_alert(data) ⇒ Object



410
411
412
413
414
415
# File 'lib/msf/core/exploit/remote/rdp.rb', line 410

def rdp_handle_license_error_alert(data)
  error_code, state_transition, error_info = data[0..11].unpack("VVV")
  vprint_status("License error/alert code 0x#{error_code.to_s(16)} (#{RDPConstants::LICENSE_ERRS[error_code]})")
  # Ensure that we were issued a license by the server
  raise RdpCommunicationError if error_code != RDPConstants::LICENSE_ERR_LICENSE_ISSUED
end

#rdp_handle_license_request(data) ⇒ Object



396
397
398
399
400
401
402
403
404
405
406
407
408
# File 'lib/msf/core/exploit/remote/rdp.rb', line 396

def rdp_handle_license_request(data)
  # Note: license_key is currently unused
  client_random, license_key, license_sign_key = rdp_generate_license_keys(data)

  # We're not really decrypting the license from the server, but it should be good enough
  vprint_status("Sending new license request PDU")
  new_license_request = pdu_new_license_request(client_random, @user_name, @computer_name)
  pkt = rdp_build_pkt(new_license_request, license_info: true)

  # Expect that we are issued a license here
  res = rdp_send_recv(pkt)
  rdp_parse_license_pdu(res)
end

#rdp_handle_packet(pkt) ⇒ Object (protected)



1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1397

def rdp_handle_packet(pkt)
  if pkt && pkt[0] == "\x03"
    if pkt[4..6] == "\x02\xf0\x80"
      if pkt[7] == "\x68"
        chan_user_id = pkt[8..9].unpack('S>')[0]
        chan_id = pkt[10..11].unpack('S>')[0]
        flags = pkt[18..21].unpack('<L')[0]
        data = pkt[22..pkt.length]
        rdp_on_channel_receive(pkt, chan_user_id, chan_id, flags, data)
      end
    end
  end
end

#rdp_hmac(mac_salt_key, data_content) ⇒ Object

docs.microsoft.com/en-us/openspecs/windows_protocols/ms-rdpbcgr/7c61b54e-f6cd-4819-a59a-daf200f6bf94 mac_salt_key = “Wx13xc58x7fxebxa9x10*x1exddVx96x8b[d” data_content = “x12x00x17x00xefx03xeax03x02x00x00x01x04x00$x00x00x00” hmac = rdp_hmac(mac_salt_key, data_content) # == hexlified: “22d5aeb486994a0c785dc929a2855923”



578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
# File 'lib/msf/core/exploit/remote/rdp.rb', line 578

def rdp_hmac(mac_salt_key, data_content)
  sha1 = Digest::SHA1.new
  md5 = Digest::MD5.new

  pad1 = "\x36" * 40
  pad2 = "\x5c" * 48

  sha1 << mac_salt_key
  sha1 << pad1
  sha1 << [data_content.length].pack('<L')
  sha1 << data_content

  md5 << mac_salt_key
  md5 << pad2
  md5 << [sha1.hexdigest].pack("H*")

  [md5.hexdigest].pack("H*")
end

#rdp_move_mouse(x = 1, y = 1) ⇒ Object



486
487
488
489
490
491
492
493
# File 'lib/msf/core/exploit/remote/rdp.rb', line 486

def rdp_move_mouse(x = 1, y = 1)
  mouse_move_blob = ""
  mouse_move_blob << "\x04\x80\x0a"    # copypasta FAST PATH stuff from xfreerdp
  mouse_move_blob << "\x20"            # TS_FP_INPUT_EVENT::eventHeader = 0x20 (FASTPATH_INPUT_EVENT_MOUSE)
  mouse_move_blob << "\x00\x08"        # TS_FP_POINTER_EVENT::pointerFlags  = 0x0800 (PTRFLAGS_MOVE)
  mouse_move_blob << [x, y].pack('vv') # TS_FP_POINTER_EVENT::xPos, TS_FP_POINTER_EVENT::yPos
  rdp_send(mouse_move_blob)
end

#rdp_negotiate_security(channels, req_proto = RDPConstants::PROTOCOL_SSL) ⇒ Boolean

Negotiate security protocol and begin session building

Returns:

  • (Boolean)

    success



330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
# File 'lib/msf/core/exploit/remote/rdp.rb', line 330

def rdp_negotiate_security(channels, req_proto = RDPConstants::PROTOCOL_SSL)
  if req_proto == RDPConstants::PROTOCOL_SSL
    swap_sock_plain_to_ssl
    res = rdp_send_recv(pdu_connect_initial(channels, req_proto, @computer_name))
  elsif req_proto == RDPConstants::PROTOCOL_RDP
    res = rdp_send_recv(pdu_connect_initial(channels, req_proto, @computer_name))
    rsmod, rsexp, _rsran, server_rand, bitlen = rdp_parse_connect_response(res)
  elsif [RDPConstants::PROTOCOL_HYBRID, RDPConstants::PROTOCOL_HYBRID_EX].include?(req_proto)
    vprint_status("NLA Security protocol unsupported at this time.")
    return false
  else
    vprint_error("Unknown protocol requested (#{req_proto}).")
    return false
  end

  # erect domain and attach user
  vprint_status("Sending erect domain request")
  rdp_send(pdu_erect_domain_request)
  res = rdp_send_recv(pdu_attach_user_request)

  self.rdp_user_id = res[9, 2].unpack("n").first

  # send channel requests
  [1009, 1003, 1004, 1005, 1006, 1007, 1008].each do |chan|
    rdp_send_recv(pdu_channel_join_request(self.rdp_user_id, chan))
  end

  if req_proto == RDPConstants::PROTOCOL_RDP
    @rdp_sec = true

    # 5.3.4 Client Random Value
    client_rand = ''
    32.times { client_rand << rand(0..255) }
    rcran = bytes_to_bignum(client_rand)

    vprint_status("Sending security exchange PDU")
    rdp_send(pdu_security_exchange(rcran, rsexp, rsmod, bitlen))

    # We aren't decrypting anything at this point. Leave the variables here
    # to make it easier to understand in the future.
    rc4encstart, _rc4decstart, @hmackey, _sessblob = rdp_calculate_rc4_keys(client_rand, server_rand)

    @rc4enckey = RC4.new(rc4encstart)
  end

  return true
end

#rdp_on_channel_receive(pkt, chan_user_id, chan_id, flags, data) ⇒ Object (protected)



1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1411

def rdp_on_channel_receive(pkt, chan_user_id, chan_id, flags, data)
  ctype = data[0..1].unpack('S')[0]

  if ctype == RDPConstants::RDPDR_CTYP_CORE
    opcode = data[2..3].unpack('S')[0]
    if opcode == RDPConstants::PAKID_CORE_SERVER_ANNOUNCE
      rdp_on_core_server_announce(pkt, chan_user_id, chan_id, flags, data)
    elsif opcode == RDPConstants::PAKID_CORE_SERVER_CAPABILITY
      rdp_on_core_server_capability(pkt, chan_user_id, chan_id, flags, data)
    elsif opcode == RDPConstants::PAKID_CORE_CLIENTID_CONFIRM
      rdp_on_core_client_id_confirm(pkt, chan_user_id, chan_id, flags, data)
    end
  end
end

#rdp_on_core_client_id_confirm(pkt, chan_user_id, chan_id, flags, data) ⇒ Object (protected)



1440
1441
1442
1443
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1440

def rdp_on_core_client_id_confirm(pkt, chan_user_id, chan_id, flags, data)
  vprint_status("Handling CLIENT ID CONFIRM ...")
  rdpdr_client_device_list_announce_request(pkt, chan_user_id, chan_id, flags, data)
end

#rdp_on_core_server_announce(pkt, chan_user_id, chan_id, flags, data) ⇒ Object (protected)



1426
1427
1428
1429
1430
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1426

def rdp_on_core_server_announce(pkt, chan_user_id, chan_id, flags, data)
  vprint_status("Handling SERVER ANNOUNCE ...")
  rdpdr_client_announce_reply(pkt, chan_user_id, chan_id, flags, data)
  rdpdr_client_name_request(pkt, chan_user_id, chan_id, flags, data)
end

#rdp_on_core_server_capability(pkt, chan_user_id, chan_id, flags, data) ⇒ Object (protected)



1432
1433
1434
1435
1436
1437
1438
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1432

def rdp_on_core_server_capability(pkt, chan_user_id, chan_id, flags, data)
  vprint_status("Handling SERVER CAPABILITY ...")
  # change opcode 1 byte to match server capabilities
  reply = [data[0..2], "\x43", data[4..data.length]].join('')

  rdp_send_channel(chan_user_id, chan_id, reply)
end

#rdp_parse_connect_response(pkt) ⇒ Object



529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
# File 'lib/msf/core/exploit/remote/rdp.rb', line 529

def rdp_parse_connect_response(pkt)
  ptr = 0
  rdp_pkt = pkt[0x49..pkt.length]

  while ptr < rdp_pkt.length
    header_type = rdp_pkt[ptr..ptr + 1]
    header_length = rdp_pkt[ptr + 2..ptr + 3].unpack("S<")[0]

    if header_type == "\x02\x0c"

      server_random = rdp_pkt[ptr + 20..ptr + 51]
      public_exponent = rdp_pkt[ptr + 84..ptr + 87]

      rsa_magic = rdp_pkt[ptr + 68..ptr + 71]
      if rsa_magic != "RSA1"
        print_error("Server cert isn't RSA, this scenario isn't supported (yet).")
        raise RdpCommunicationError
      end

      bitlen = rdp_pkt[ptr + 72..ptr + 75].unpack("L<")[0] - 8
      modulus = rdp_pkt[ptr + 88..ptr + 87 + bitlen]
    end

    ptr += header_length
  end

  # vprint_status("SERVER_MODULUS: #{bin_to_hex(modulus)}")
  # vprint_status("SERVER_EXPONENT: #{bin_to_hex(public_exponent)}")
  # vprint_status("SERVER_RANDOM: #{bin_to_hex(server_random)}")

  rsmod = bytes_to_bignum(modulus)
  rsexp = bytes_to_bignum(public_exponent)
  rsran = bytes_to_bignum(server_random)

  # vprint_status("MODULUS  = #{bin_to_hex(modulus)} - #{rsmod.to_s}")
  # vprint_status("EXPONENT = #{bin_to_hex(public_exponent)} - #{rsexp.to_s}")
  # vprint_status("SVRANDOM = #{bin_to_hex(server_random)} - #{rsran.to_s}")

  return rsmod, rsexp, rsran, server_random, bitlen
end

#rdp_parse_license_pdu(data) ⇒ Object



417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
# File 'lib/msf/core/exploit/remote/rdp.rb', line 417

def rdp_parse_license_pdu(data)
  raise RdpCommunicationError if data.length < 20
  rdp_version = data[0].unpack("C")[0]
  raise RdpCommunicationError if rdp_version != 3
  length = data[2..3].unpack("n")[0]
  if data.length < length
    vprint_error("Got #{data.length} bytes, expected #{length}")
    raise RdpCommunicationError
  end

  data_len = data[13].unpack("C")[0]
  tag_offset = 18
  tag_offset += 1 if (data_len & 0x80 == 0x80) # 2 byte length

  tag = data[tag_offset].unpack("C")[0]
  vprint_status("Got license packet type 0x#{tag.to_s(16)} (#{RDPConstants::LICENSE_TAGS[tag]})")

  case tag
    when RDPConstants::LICENSE_REQUEST
      rdp_handle_license_request(data[tag_offset + 4..-1])
    when RDPConstants::LICENSE_PLATFORM_CHALLENGE
    when RDPConstants::LICENSE_NEW_LICENSE
    when RDPConstants::LICENSE_UPGRADE_LICENSE
    when RDPConstants::LICENSE_LICENSE_INFO
    when RDPConstants::LICENSE_NEW_LICENSE_REQ
    when RDPConstants::LICENSE_PLATFORM_CHAL_RESP
    when RDPConstants::LICENSE_ERROR_ALERT
      rdp_handle_license_error_alert(data[tag_offset + 4..-1])
  end
end

#rdp_parse_negotiation_response(data) ⇒ String?

Returns:

  • (String, nil)

    String representation of the Selected Protocol or nil on failure

  • (String)

    Error message



503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
# File 'lib/msf/core/exploit/remote/rdp.rb', line 503

def rdp_parse_negotiation_response(data)
  return false, "Response is not an RDP Negotiation Response packet." unless data.match("\x03\x00\x00..\xd0")
  return false, "Negotiation Response packet too short." if data.length < 19

  response_code = data[11].unpack("C")[0]

  if response_code == 2  # TYPE_RDP_NEG_RSP
    # RDP Negotiation Response - 2.2.1.2.1
    server_selected_proto = data[15..18].unpack("L<")[0]

    proto_label = RDPConstants::RDP_NEG_PROTOCOL[server_selected_proto]
    return server_selected_proto, nil if proto_label

    return nil, "Unknown protocol in Negotiation Response: #{server_selected_proto}"

  elsif response_code == 3  # TYPE_RDP_NEG_FAILURE
    # RDP Negotiation Failure - 2.2.1.2.2
    failure_code = data[15..18].unpack("L<")[0]
    return nil, RDPConstants::RDP_NEG_FAILURE[failure_code]
  else
    return nil, "Unknown Negotiation Response code: #{response_code}"
  end
end

#rdp_rc4_crypt(rc4obj, data) ⇒ Object



668
669
670
# File 'lib/msf/core/exploit/remote/rdp.rb', line 668

def rdp_rc4_crypt(rc4obj, data)
  rc4obj.encrypt(data)
end

#rdp_recv(length = -1,, timeout = 5) ⇒ Object



157
158
159
160
161
162
163
164
# File 'lib/msf/core/exploit/remote/rdp.rb', line 157

def rdp_recv(length = -1, timeout = 5)
  res = self.rdp_sock.get_once(length, timeout)
  raise RdpCommunicationError unless res # nil due to a timeout

  res
rescue EOFError
  raise RdpCommunicationError
end

#rdp_salted_hash(s_bytes, i_bytes, client_random_bytes, server_random_bytes) ⇒ Object

docs.microsoft.com/en-us/openspecs/windows_protocols/ms-rdpbcgr/705f9542-b0e3-48be-b9a5-cf2ee582607f

SaltedHash(S, I) = MD5(S + SHA(I + S + ClientRandom + ServerRandom))


609
610
611
612
613
614
615
616
617
618
619
620
621
622
# File 'lib/msf/core/exploit/remote/rdp.rb', line 609

def rdp_salted_hash(s_bytes, i_bytes, client_random_bytes, server_random_bytes)
  sha1 = Digest::SHA1.new
  md5 = Digest::MD5.new

  sha1 << i_bytes
  sha1 << s_bytes
  sha1 << client_random_bytes
  sha1 << server_random_bytes

  md5 << s_bytes
  md5 << [sha1.hexdigest].pack("H*")

  [md5.hexdigest].pack("H*")
end

#rdp_salted_hash16(s_bytes, salt1, salt2) ⇒ Object



597
598
599
600
601
602
603
604
605
# File 'lib/msf/core/exploit/remote/rdp.rb', line 597

def rdp_salted_hash16(s_bytes, salt1, salt2)
  md5 = Digest::MD5.new

  md5 << s_bytes[0..15]
  md5 << salt1[0..31]
  md5 << salt2[0..31]

  [md5.hexdigest].pack("H*")
end

#rdp_salted_hash48(s_bytes, i_byte, client_random, server_random) ⇒ Object



624
625
626
627
628
# File 'lib/msf/core/exploit/remote/rdp.rb', line 624

def rdp_salted_hash48(s_bytes, i_byte, client_random, server_random)
  rdp_salted_hash(s_bytes, i_byte, client_random, server_random) + \
    rdp_salted_hash(s_bytes, (i_byte.ord + 1).chr * 2, client_random, server_random) + \
    rdp_salted_hash(s_bytes, (i_byte.ord + 2).chr * 3, client_random, server_random)
end

#rdp_send(data) ⇒ Object



153
154
155
# File 'lib/msf/core/exploit/remote/rdp.rb', line 153

def rdp_send(data)
  self.rdp_sock.put(data)
end

#rdp_send_channel(chan_user_id, chan_id, data, flags = 3, data_length = nil) ⇒ Object



242
243
244
245
# File 'lib/msf/core/exploit/remote/rdp.rb', line 242

def rdp_send_channel(chan_user_id, chan_id, data, flags = 3, data_length = nil)
  tpkt = rdp_create_channel_msg(chan_user_id, chan_id, data, flags, data_length)
  rdp_send(tpkt)
end

#rdp_send_recv(data) ⇒ Object



166
167
168
169
# File 'lib/msf/core/exploit/remote/rdp.rb', line 166

def rdp_send_recv(data)
  rdp_send(data)
  rdp_recv
end

#rdp_terminateObject



247
248
249
250
251
# File 'lib/msf/core/exploit/remote/rdp.rb', line 247

def rdp_terminate
  body = "\x21\x80" # user requested disconnect provider ultimatum

  rdp_send(build_data_tpdu(body))
end

#rdpdr_client_announce_reply(pkt, chan_user_id, chan_id, flags, data) ⇒ Object (protected)



1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1455

def rdpdr_client_announce_reply(pkt, chan_user_id, chan_id, flags, data)
  reply = [
    RDPConstants::RDPDR_CTYP_CORE,
    RDPConstants::PAKID_CORE_CLIENTID_CONFIRM,
    0x1, # Version Major
    0xc, # Version Minor
    0x2, # client ID (TODO: configure this? read it from the packet?
  ].pack('SSSSL')

  rdp_send_channel(chan_user_id, chan_id, reply)
end

#rdpdr_client_device_list_announce_request(pkt, chan_user_id, chan_id, flags, data) ⇒ Object (protected)



1445
1446
1447
1448
1449
1450
1451
1452
1453
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1445

def rdpdr_client_device_list_announce_request(pkt, chan_user_id, chan_id, flags, data)
  reply = [
    RDPConstants::RDPDR_CTYP_CORE,
    RDPConstants::PAKID_CORE_DEVICELIST_ANNOUNCE,
    0x0, # Device count
  ].pack('SSL')

  rdp_send_channel(chan_user_id, chan_id, reply)
end

#rdpdr_client_name_request(pkt, chan_user_id, chan_id, flags, data) ⇒ Object (protected)



1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1467

def rdpdr_client_name_request(pkt, chan_user_id, chan_id, flags, data)
  computer_name = Rex::Text.to_unicode("#{@computer_name}\x00", 'utf-16le')
  reply = [
    RDPConstants::RDPDR_CTYP_CORE,
    RDPConstants::PAKID_CORE_CLIENT_NAME,
    0x1, # Unicode flag
    0x0, # Code Page
    computer_name.length,
    computer_name,
  ].pack('SSLLLa*')

  rdp_send_channel(chan_user_id, chan_id, reply)
end

#rsa_encrypt(bignum, rsexp, rsmod) ⇒ Object



664
665
666
# File 'lib/msf/core/exploit/remote/rdp.rb', line 664

def rsa_encrypt(bignum, rsexp, rsmod)
  (bignum ** rsexp) % rsmod
end

#swap_sock_plain_to_sslObject

Create a new SSL session on the existing socket. Stolen from exploit/smtp_deliver.rb



1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
# File 'lib/msf/core/exploit/remote/rdp.rb', line 1171

def swap_sock_plain_to_ssl
  ctx = OpenSSL::SSL::SSLContext.new
  ctx.min_version = OpenSSL::SSL::TLS1_VERSION
  ctx.security_level = datastore['RDP_TLS_SECURITY_LEVEL']
  ssl = OpenSSL::SSL::SSLSocket.new(self.rdp_sock, ctx)

  begin
    ssl.connect
  rescue Errno::ECONNRESET
    vprint_error("Retry with advanced option RDP_TLS_SECURITY_LEVEL=0")
    raise
  end

  self.rdp_sock.extend(Rex::Socket::SslTcp)
  self.rdp_sock.sslsock = ssl
  self.rdp_sock.sslctx  = ctx
end