The conceptions of warfare and battlefield have astonishingly evolved, going from a traditional view of military ammunition performed in land, sea or air, to the most novel electronic devices which rule today’s international conflict strategies in cyberspace. Some examples of the latter weapons operating in the so-called fifth domain, like pen drives, drone strikes, keyboards and malware, are even considered innocuous at the first glimpse, especially when compared to other type of classic artillery. Howbeit, these gadgets were the ones that fostered the current limitless cyber race – which was noticeably triggered by the cyber attack occurred in Estonia (2007) – and has since then proved capable of causing way more alarming consequences, mainly if targeting critical national infrastructures. This present dissertation will dwell on the analysis of the enforcement of international law bodies towards acts of cyber war carried out by state or non-state agents, taking into specific consideration the application of the international criminal law norms. Thereunder, the focus of the study will remain on the characterization of cyber attacks, as either potential crimes of war or aggression