Cyber attacks present one of several new challenges to global, national and personal security that result from cyber space weapons development and deployment. These new threats are a daily occurrence in every country. Nonetheless, much ambivalence remains in both international and Israeli law regarding its definition and ramifications. This ambivalence has so far curtailed the development of definitive normative prescriptions applicable to cyber terrorism. Nonetheless, a present focus of threat assessment is the vulnerability of critical infrastructures and networks to cyber terrorism attacks. In this article, the emerging international legal norms prohibiting cyber terrorism will be examined; and the relevant provisions of Israeli legislation will be analyzed in a comparative context.