vendor/bundle/ruby/2.4.0/gems/safe_yaml-1.0.4/spec/support/exploitable_back_door.rb

class ExploitableBackDoor
  def exploited?
    @exploited_through_setter || @exploited_through_init_with || @exploited_through_ivars
  end

  def exploited_through_setter?
    @exploited_through_setter
  end

  def exploited_through_init_with?
    @exploited_through_init_with
  end

  def exploited_through_ivars?
    self.instance_variables.any?
  end

  def init_with(command)
    # Note: this is how bad this COULD be.
    # system("#{command}")
    @exploited_through_init_with = true
  end

  def []=(command, arguments)
    # Note: this is how bad this COULD be.
    # system("#{command} #{arguments}")
    @exploited_through_setter = true
  end
end