Cislunar space is rapidly emerging as a critical domain for commercial, scientific, and national security activities, necessitating robust cybersecurity frameworks for its networked infrastructure. Unlike traditional Low Earth Orbit (LEO) and Geostationary Orbit (GEO) assets, cislunar spacecraft must operate autonomously in a resource-constrained, high-risk environment. These systems depend on secure inter-satellite links (ISLs), AI-driven autonomy, and resilient edge computing while also introducing new cyber vulnerabilities such as ISL hijacking, adversarial machine learning attacks, and interference jamming.

The increasing complexity of cislunar networks demands novel cybersecurity strategies. Threat actors, including state-sponsored entities and independent adversaries, may exploit vulnerabilities in communication, navigation, and data processing systems. This paper examines cybersecurity challenges unique to cislunar operations, focusing on secure network topology management, real-time intrusion detection, and autonomous threat mitigation. This paper presents security constructs and their relationship to cislunar operations and associated technology. Building on this, we propose a threat scenario that is unique to cislunar space which serves to contextualize the novel challenges of the research domain. The threat scenario prompts future work in cislunar malware development as a proof of concept, along with associated defensive capabilities highlighting the need for further technology development unique to the domain.