Resumen:
Peacetime cyberattacks by groups of hacktivists, transnational criminal organizations or terrorist groups, increase every year, being the most frequent cyber threat against States' IT infrastructures. Given this reality, the international community does not have developed yet an effective legal tool in order to attribute international responsibility to those States from whose territory non-State actors launch their cyberattacks against other countries. Therefore, this article suggests that the adoption of the cyber-due diligence concept - based on the classic notion of due diligence - would make easier to identify responsible States and attribute them their responsibility for failing to adopt preventive measures, such as monitoring activities.