Share
## https://sploitus.com/exploit?id=PACKETSTORM:181008
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Auxiliary
include Msf::Exploit::Remote::Smtp
include Msf::Auxiliary::Scanner
include Msf::Auxiliary::Report
def initialize
super(
'Name' => 'SMTP Open Relay Detection',
'Description' => %q{
This module tests if an SMTP server will accept (via a code 250)
an e-mail by using a variation of testing methods.
Some of the extended methods will try to abuse configuration or mailserver flaws.
},
'References' =>
[
['URL', 'http://www.ietf.org/rfc/rfc2821.txt'],
['URL', 'https://svn.nmap.org/nmap/scripts/smtp-open-relay.nse'],
],
'Author' =>
[
'Campbell Murray',
'xistence <xistence[at]0x90.nl>',
],
'License' => MSF_LICENSE
)
register_options(
[
OptBool.new('EXTENDED', [true, 'Do all the 16 extended checks', false]),
])
end
def run_host(ip)
begin
connect
banner_sanitized = Rex::Text.to_hex_ascii(banner.to_s)
print_good("SMTP #{banner_sanitized}")
report_service(:host => rhost, :port => rport, :name => "smtp", :info => banner)
if datastore['EXTENDED']
if banner_sanitized =~ /220 (.*) /
serverhost = $1
end
mailfromuser = datastore['MAILFROM'].split("@").first
mailfromdomain = datastore['MAILFROM'].split("@").last
mailtouser = datastore['MAILTO'].split("@").first
mailtodomain = datastore['MAILTO'].split("@").last
do_test_relay(1, "MAIL FROM:<>", "RCPT TO:<#{datastore['MAILTO']}>")
do_test_relay(2, "MAIL FROM:<#{datastore['MAILFROM']}>", "RCPT TO:<#{datastore['MAILTO']}>")
do_test_relay(3, "MAIL FROM:<#{mailfromuser}@#{serverhost}>", "RCPT TO:<#{datastore['MAILTO']}>")
do_test_relay(4, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtouser}@[#{rhost}]>")
do_test_relay(5, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtouser}\%#{mailtodomain}@[#{rhost}]>")
do_test_relay(6, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtouser}\%#{mailtodomain}@#{serverhost}>")
do_test_relay(7, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<\"#{mailtouser}@#{mailtodomain}\">")
do_test_relay(8, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<\"#{mailtouser}\%#{mailtodomain}\">")
do_test_relay(9, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtouser}@#{mailtodomain}@[#{rhost}]>")
do_test_relay(10, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<\"#{mailtouser}@#{mailtodomain}\"@[#{rhost}]>")
do_test_relay(11, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtouser}@#{mailtodomain}@#{serverhost}>")
do_test_relay(12, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<@[#{rhost}]:#{mailtouser}@#{mailtodomain}>")
do_test_relay(13, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<@#{serverhost}:#{mailtouser}@#{mailtodomain}>")
do_test_relay(14, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtodomain}!#{mailtouser}>")
do_test_relay(15, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtodomain}!#{mailtouser}@[#{rhost}]>")
do_test_relay(16, "MAIL FROM:<#{mailfromuser}@[#{rhost}]>", "RCPT TO:<#{mailtodomain}!#{mailtouser}@#{serverhost}>")
else
do_test_relay(nil, "MAIL FROM:<#{datastore['MAILFROM']}>", "RCPT TO:<#{datastore['MAILTO']}>")
end
rescue
print_error("Unable to establish an SMTP session")
return
end
end
def do_test_relay(testnumber, mailfrom, mailto)
begin
connect
res = raw_send_recv("EHLO X\r\n")
vprint_status("#{res.inspect}")
# check if the EHLO is actually supported. In case it's not, try the HELO command instead
if res.to_s =~ /^5\d\d/
res = raw_send_recv("HELO X\r\n")
vprint_status("#{res.inspect}")
end
res = raw_send_recv("#{mailfrom}\r\n")
vprint_status("#{res.inspect}")
res = raw_send_recv("#{mailto}\r\n")
vprint_status("#{res.inspect}")
res = raw_send_recv("DATA\r\n")
vprint_status("#{res.inspect}")
res = raw_send_recv("#{Rex::Text.rand_text_alpha(rand(10)+5)}\r\n.\r\n")
vprint_status("#{res.inspect}")
if res =~ /250/
if testnumber.nil?
print_good("Potential open SMTP relay detected: - #{mailfrom} -> #{mailto}")
else
print_good("Test ##{testnumber} - Potential open SMTP relay detected: - #{mailfrom} -> #{mailto}")
end
else
if testnumber.nil?
print_status "No relay detected"
else
print_status "Test ##{testnumber} - No relay detected"
end
end
rescue
print_error("Test ##{testnumber} - Unable to establish an SMTP session")
return
end
end
end