modules/auxiliary/fuzzers/smb/smb_negotiate_corrupt.rb
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Auxiliary
include Msf::Exploit::Remote::Tcp
include Msf::Auxiliary::Fuzzer
def initialize(info = {})
super(update_info(info,
'Name' => 'SMB Negotiate Dialect Corruption',
'Description' => %q{
This module sends a series of SMB negotiate requests with corrupted bytes
},
'Author' => [ 'hdm' ],
'License' => MSF_LICENSE
))
register_options([
Opt::RPORT(445),
OptInt.new('MAXDEPTH', [false, 'Specify a maximum byte depth to test'])
])
end
def do_smb_negotiate(pkt,opts={})
@connected = false
connect
@connected = true
sock.put(pkt)
sock.get_once(-1, opts[:timeout])
end
def run
last_str = nil
last_inp = nil
last_err = nil
pkt = make_smb_negotiate
cnt = 0
max = datastore['MAXDEPTH'].to_i
max = nil if max == 0
tot = ( max ? [max,pkt.length].min : pkt.length) * 256
print_status("Fuzzing SMB negotiate packet with #{tot} requests")
fuzz_string_corrupt_byte_reverse(pkt,max) do |str|
cnt += 1
if(cnt % 100 == 0)
print_status("Fuzzing with iteration #{cnt}/#{tot} using #{@last_fuzzer_input}")
end
begin
r = do_smb_negotiate(str, 0.25)
rescue ::Interrupt
print_status("Exiting on interrupt: iteration #{cnt} using #{@last_fuzzer_input}")
raise $!
rescue ::Exception => e
last_err = e
ensure
disconnect
end
if(not @connected)
if(last_str)
print_status("The service may have crashed: iteration:#{cnt-1} method=#{last_inp} string=#{last_str.unpack("H*")[0]} error=#{last_err}")
else
print_status("Could not connect to the service: #{last_err}")
end
return
end
last_str = str
last_inp = @last_fuzzer_input
end
end
def make_smb_negotiate
# The SMB 2 dialect must be there
dialects = ['PC NETWORK PROGRAM 1.0', 'LANMAN1.0', 'Windows for Workgroups 3.1a', 'LM1.2X002', 'LANMAN2.1', 'NT LM 0.12']
data = dialects.collect { |dialect| "\x02" + dialect + "\x00" }.join('')
pkt = Rex::Proto::SMB::Constants::SMB_NEG_PKT.make_struct
pkt['Payload']['SMB'].v['Command'] = Rex::Proto::SMB::Constants::SMB_COM_NEGOTIATE
pkt['Payload']['SMB'].v['Flags1'] = 0x18
pkt['Payload']['SMB'].v['Flags2'] = 0xc853
pkt['Payload'].v['Payload'] = data
pkt.to_s
end
end