Class: Cross::Engine

Inherits:
Object
  • Object
show all
Includes:
Singleton
Defined in:
lib/cross/engine.rb

Overview

Engine is the cross class using Mechanize to inject canary and check for output

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#agent ⇒ Object (readonly)

Returns the value of attribute agent.



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# File 'lib/cross/engine.rb', line 13

def agent
  @agent
end

#options ⇒ Object

Returns the value of attribute options.



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# File 'lib/cross/engine.rb', line 14

def options
  @options
end

Instance Method Details

#authenticate? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/cross/engine.rb', line 28

def authenticate?
  ! @options[:auth].nil?  and ! @options[:auth].empty? 
end

#crawl(url) ⇒ Object 



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# File 'lib/cross/engine.rb', line 36

def crawl(url)
  start if @agent.nil?

  links = []
  @agent.add_auth(url, @options[:auth][:username], @options[:auth][:password]) if authenticate?
  begin 
    page=@agent.get(url)
    page=@agent.get(url) if authenticate?
    page.links.each do |l|
      @agent.log.debug("Link found: #{l.href}") if debug?
      links << l.href
    end
  rescue Mechanize::UnauthorizedError
    return {:status=>'KO', :links=>[], :message=>'target website requires authentication'}
  rescue => e 
    return {:status=>'KO', :links=>links, :message=>e.to_s}
  end

  return {:status=>'OK', :links=>links, :message=>''}
end

#crawl? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/cross/engine.rb', line 32

def crawl?
  @options[:crawl][:enabled]
end

#debug? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/cross/engine.rb', line 16

def debug?
  @options[:debug]
end

#inject(url) ⇒ Object 



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# File 'lib/cross/engine.rb', line 57

def inject(url)
  start if @agent.nil?

  $logger.log "Authenticating to the app using #{@options[:auth][:username]}:#{@options[:auth][:password]}" if debug?

  @agent.add_auth(url, @options[:auth][:username], @options[:auth][:password]) if authenticate?

  found = false
  if @options[:exploit_url]
    # You ask to exploit the url, so I won't check for form values

    attack_url = Cross::Url.new(url)

    Cross::Attack::XSS.each do |pattern|
      attack_url.params.each do |par|

        page = @agent.get(attack_url.fuzz(par[:name],pattern))
        @agent.log.debug(page.body) if debug?

        scripts = page.search("//script")
        scripts.each do |sc|
          $logger.log(page.body) if @options[:debug] if sc.children.text.include?("alert(#{Cross::Attack::XSS::CANARY})")
          return true if sc.children.text.include?("alert(#{Cross::Attack::XSS::CANARY})")
        end

        return false if options[:oneshot]

        attack_url.reset
      end
    end

  else
    begin
      page = @agent.get(url)
    rescue Mechanize::UnauthorizedError
      $logger.err 'Authentication failed. Giving up.'
      return false
    rescue Mechanize::ResponseCodeError
      $logger.err 'Server gave back 404. Giving up.'
      return false
    rescue Net::HTTP::Persistent::Error => e
      $logger.err e.message
      return false
    end

    $logger.log "#{page.forms.size} form(s) found" if debug?

    Cross::Attack::XSS.each do |pattern|

      $logger.log "using attack vector: #{pattern}" if debug?


      page.forms.each do |f|
        f.fields.each do |ff|
          if  options[:sample_post].empty?
            ff.value = pattern if options[:parameter_to_tamper].empty?
            ff.value = pattern if ! options[:parameter_to_tamper].empty? && ff.name==options[:parameter_to_tamper]
          else
            ff.value = find_sample_value_for(options[:sample_post], ff.name) unless ff.name==options[:parameter_to_tamper]
            ff.value = pattern if ff.name==options[:parameter_to_tamper]

          end
        end

        pp = @agent.submit(f)
        $logger.log "header: #{pp.header}" if debug? && ! pp.header.empty?
        $logger.log "body: #{pp.body}" if debug? && ! pp.body.empty?
        $logger.err "Page is empty" if pp.body.empty?
        scripts = pp.search("//script")
        scripts.each do |sc|
          return true if sc.children.text.include?("alert(#{Cross::Attack::XSS::CANARY})")
        end

        # This is for input html field javascript event evasion
        inputs = pp.search("//input")
        inputs.each do |input|
          return true if ! input['onmouseover'].nil? && input['onmouseover'].include?("alert(#{Cross::Attack::XSS::CANARY})") 
        end
      end 
      return false if options[:oneshot]
    end
  end
  found
end

#start(options = {:exploit_url=>false, :debug=>false, :auth=>{}}) ⇒ Object

Starts the engine



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# File 'lib/cross/engine.rb', line 21

def start(options={:exploit_url=>false, :debug=>false, :auth=>{}})
  @agent = Mechanize.new {|a| a.log = Logger.new("cross.log")}
  @agent.user_agent_alias = 'Mac Safari'
  @agent.agent.http.verify_mode = OpenSSL::SSL::VERIFY_NONE
  @options = options
end