_upnp_delete_redir(unsigned short eport, int proto)
{
	int r;
#if defined(__linux__)
	r = delete_redirect_and_filter_rules(eport, proto);
#elif defined(USE_PF)
	r = delete_redirect_and_filter_rules(ext_if_name, eport, proto);
#else
	r = delete_redirect_rule(ext_if_name, eport, proto);
	delete_filter_rule(ext_if_name, eport, proto);
#endif
#ifdef ENABLE_LEASEFILE
	lease_file_remove( eport, proto);
#endif

#ifdef ENABLE_EVENTS
	upnp_event_var_change_notify(EWanIPC);
#endif
	return r;
}

The product dereferences a pointer that it expects to be valid but is NULL.