Security Challenges in 5G Network Slicing: A Risk-Based Analysis and Conceptual Framework

Network slicing is a core enabler of multi-tenant 5th Generation (5G) architectures, allowing heterogeneous services to coexist over shared infrastructure. However, ensuring effective isolation between slices remains a critical security challenge, as failures may enable cross-slice interference, data leakage, or cascading service disruption. This article analyses security vulnerabilities affecting 5G network slicing from a risk-oriented perspective, with particular emphasis on isolation weaknesses across orchestration, virtualization, network, and interface layers. Due to the technical immaturity and instability of current open-source slicing platforms, experimental validation of security mechanisms proved infeasible. These limitations are therefore treated as empirical evidence informing a structured vulnerability taxonomy and a qualitative risk assessment grounded in confidentiality, integrity, and availability. Building on this analysis, the article proposes a conceptual security framework that integrates defence-in-depth, zero-trust principles, continuous monitoring, and adaptive response mechanisms to enforce isolation dynamically. Aligned with established standards and regulatory references, the framework provides a coherent theoretical foundation for future experimental validation and the secure design of resilient 5G network slicing architectures.