    def _auth_from_challenge(self, host, request_uri, headers, response, content):
        """A generator that creates Authorization objects
           that can be applied to requests.
        """
        challenges = _parse_www_authenticate(response, "www-authenticate")
        for cred in self.credentials.iter(host):
            for scheme in AUTH_SCHEME_ORDER:
                if scheme in challenges:
                    yield AUTH_SCHEME_CLASSES[scheme](
                        cred, host, request_uri, headers, response, content, self
                    )
The software does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.