High-Altitude Platform Station Systems Cybersecurity Analysis

This paper examines cybersecurity threats in high-altitude platform station (HAPS) systems through reference architecture and attack tree methods. Given the rising commercial and military interest in these systems to enable next-generation 6G and hybrid telecommunication architectures, the threat of cyber and electronic attacks is increasing. The study focuses on providing the complete reference architecture of an aerostatic HAPS system equipped with a hybrid free-space optical and radio frequency transponder payload to be employed as a node of a nonterrestrial network. This study investigates potential attack vectors across various subsystems by coupling the attack tree methodology with the attack surface mapping derived from the reference architecture. Recommendations for mitigating cyberthreats and a secure-by-design approach are proposed to enhance the safety of future HAPS systems.