'Tests an URLs for shell shock vulnerabilities using time delays.
:param freq: A FuzzableRequest
:return: True if a vulnerability was found'

def _with_time_delay(self, freq):

    mutant = self.create_mutant(freq, TEST_HEADER)
    for delay_obj in self.DELAY_TESTS:
        ed = ExactDelayController(mutant, delay_obj, self._uri_opener)
        (success, responses) = ed.delay_is_controlled()
        if success:
            mutant.set_token_value(delay_obj.get_string_for_delay(3))
            desc = (u'Shell    shock    was    found    at:    %s' % mutant.found_at())
            v = Vuln.from_mutant(u'Shell    shock    vulnerability', desc, severity.HIGH, [r.id for r in responses], self.get_name(), mutant)
            self.kb_append_uniq(self, 'shell_shock', v)
            return True
