This systematic literature review aims to synthesize existing research on cyberwarfare and state-sponsored hacking, with a particular focus on the insights gained from penetration testing. By consolidating and analyzing a wide range of scholarly articles, technical reports, and case studies, this review seeks to identify the primary strategies, techniques, and tools utilized by state actors in cyber operations. It explores how penetration testing can aid in understanding and mitigating these threats and highlights the motivations behind state-sponsored cyber activities, ranging from espionage and sabotage to information warfare and political disruption. Key findings reveal sophisticated tactics, techniques, and procedures (TTPs) employed by state actors, the increasing complexity and coordination of cyber operations, and the pivotal role of advanced persistent threats (APTs). The review emphasizes the valuable role of penetration testing in cybersecurity, extracting lessons on detecting, mitigating , and preventing sophisticated cyberattacks orchestrated by nation-states. It underscores the necessity for robust cybersecurity frameworks incorporating continuous testing and real-time threat intelligence, as well as the importance of international cooperation, policy formulation, and the development of advanced cybersecurity technologies. The conclusions drawn emphasize the need for continuous improvement in cybersecurity measures and future research directions, highlighting significant implications for national and organizational security.