Strengthening SUPI Security in 5G Core Networks for Non-Public Applications

This study addresses key security challenges in managing the Subscription Permanent Identifier (SUPI) within 5G Non-Public Networks (NPNs). Existing 3GPP standards, optimized for public networks, leave private networks vulnerable to risks such as unauthorized SUPI access and systematic guessing attacks. To address these issues, we propose several enhancements, including adaptive access controls, measures to prevent the vulnerabilities associated with the null-scheme, and the adoption of post-quantum cryptography to safeguard sensitive subscriber data. Our methodology combines simulation-based vulnerability assessments with targeted countermeasures to reduce SUPI-related security risks. The results highlight a significant reduction in potential attack vectors, providing practical recommendations for improving privacy and data security within 5G NPNs. By aligning with ongoing 3GPP standardization efforts, our work offers a forward-looking framework to mitigate emerging threats, particularly as quantum computing becomes a critical concern.