1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
local datetime = require "datetime"
local os = require "os"
local smtp = require "smtp"
local shortport = require "shortport"
local stdnse = require "stdnse"
local base64 = require "base64"
local smbauth = require "smbauth"
local string = require "string"
description = [[
This script enumerates information from remote SMTP services with NTLM
authentication enabled.
Sending a SMTP NTLM authentication request with null credentials will
cause the remote service to respond with a NTLMSSP message disclosing
information to include NetBIOS, DNS, and OS build version.
]]
---
-- @usage
-- nmap -p 25,465,587 --script smtp-ntlm-info --script-args smtp-ntlm-info.domain=domain.com <target>
--
-- @output
-- 25/tcp open smtp
-- | smtp-ntlm-info:
-- | Target_Name: ACTIVESMTP
-- | NetBIOS_Domain_Name: ACTIVESMTP
-- | NetBIOS_Computer_Name: SMTP-TEST2
-- | DNS_Domain_Name: somedomain.com
-- | DNS_Computer_Name: smtp-test2.somedomain.com
-- | DNS_Tree_Name: somedomain.com
-- |_ Product_Version: 6.1.7601
--
--@xmloutput
-- <elem key="Target_Name">ACTIVESMTP</elem>
-- <elem key="NetBIOS_Domain_Name">ACTIVESMTP</elem>
-- <elem key="NetBIOS_Computer_Name">SMTP-TEST2</elem>
-- <elem key="DNS_Domain_Name">somedomain.com</elem>
-- <elem key="DNS_Computer_Name">smtp-test2.somedomain.com</elem>
-- <elem key="DNS_Tree_Name">somedomain.com</elem>
-- <elem key="Product_Version">6.1.7601</elem>
author = "Justin Cacak"
license = "Same as Nmap--See https://nmap.org/book/man-legal.html"
categories = {"default", "discovery", "safe"}
local ntlm_auth_blob = base64.enc( select(2,
smbauth.get_security_blob(nil, nil, nil, nil, nil, nil, nil,
0x00000001 + -- Negotiate Unicode
0x00000002 + -- Negotiate OEM strings
0x00000004 + -- Request Target
0x00000200 + -- Negotiate NTLM
0x00008000 + -- Negotiate Always Sign
0x00080000 + -- Negotiate NTLM2 Key
0x20000000 + -- Negotiate 128
0x80000000 -- Negotiate 56
))
)
portrule = shortport.port_or_service({ 25, 465, 587 }, { "smtp", "smtps", "submission" })
local function do_connect(host, port, domain)
local options = {
recv_before = true,
ssl = true,
}
local socket, response = smtp.connect(host, port, options)
if not socket then
return
end
-- Required to send EHLO
local status, response = smtp.ehlo(socket, domain)
if not status then
return
end
return socket
end
action = function(host, port)
local output = stdnse.output_table()
-- Select domain name. Typically has no implication for this purpose.
local domain = stdnse.get_script_args(SCRIPT_NAME .. ".domain") or smtp.get_domain(host)
local socket = do_connect(host, port, domain)
if not socket then
return nil
end
-- Per RFC, do not attempt to upgrade to a TLS connection if already over TLS
if not shortport.ssl(host, port) then
-- After EHLO, attempt to upgrade to a TLS connection (may not be advertised)
-- Various implementations *require* this before accepting authentication requests
local status, response = smtp.starttls(socket)
if status then
-- Read line after upgrading the connection or timeout trying.
-- This may induce a delay, however, appears required under rare conditions
-- since reconnect_ssl does not support recv_before.
-- -- commenting this out, not needed in testing, but may crop up sometime.
--status, response = socket:receive_lines(1)
-- Per RFC, must EHLO again after connection upgrade
status, response = smtp.ehlo(socket, domain)
else
-- STARTTLS failed, which means smtp.lua sent QUIT and shut down the
-- connection. Try again without SSL
socket = do_connect(host, port, domain)
end
end
socket:send("AUTH NTLM\r\n")
local status, response = socket:receive()
if not response then
return
end
socket:send(ntlm_auth_blob .. "\r\n")
status, response = socket:receive()
if not response then
return
end
local recvtime = os.time()
socket:close()
-- Continue only if a 334 response code is returned
local response_decoded = string.match(response, "^334 (.*)")
if not response_decoded then
return
end
response_decoded = base64.dec(response_decoded)
-- Continue only if NTLMSSP response is returned
if not string.match(response_decoded, "^NTLMSSP") then
return nil
end
local ntlm_decoded = smbauth.get_host_info_from_security_blob(response_decoded)
if ntlm_decoded.timestamp and ntlm_decoded.timestamp > 0 then
stdnse.debug1("timestamp is %s", ntlm_decoded.timestamp)
-- 64-bit number of 100ns clicks since 1/1/1601
local unixstamp = ntlm_decoded.timestamp // 10000000 - 11644473600
datetime.record_skew(host, unixstamp, recvtime)
end
-- Target Name will always be returned under any implementation
output.Target_Name = ntlm_decoded.target_realm
-- Display information returned & ignore responses with null values
if ntlm_decoded.netbios_domain_name and #ntlm_decoded.netbios_domain_name > 0 then
output.NetBIOS_Domain_Name = ntlm_decoded.netbios_domain_name
end
if ntlm_decoded.netbios_computer_name and #ntlm_decoded.netbios_computer_name > 0 then
output.NetBIOS_Computer_Name = ntlm_decoded.netbios_computer_name
end
if ntlm_decoded.dns_domain_name and #ntlm_decoded.dns_domain_name > 0 then
output.DNS_Domain_Name = ntlm_decoded.dns_domain_name
end
if ntlm_decoded.fqdn and #ntlm_decoded.fqdn > 0 then
output.DNS_Computer_Name = ntlm_decoded.fqdn
end
if ntlm_decoded.dns_forest_name and #ntlm_decoded.dns_forest_name > 0 then
output.DNS_Tree_Name = ntlm_decoded.dns_forest_name
end
if ntlm_decoded.os_major_version then
output.Product_Version = string.format("%d.%d.%d",
ntlm_decoded.os_major_version, ntlm_decoded.os_minor_version, ntlm_decoded.os_build)
end
return output
end
|