Modern safety-critical and real-time systems increasingly rely on multi-core architectures, which introduce shared hardware resources that can lead to inter-core interference. This interference poses risks to both security and safety, enabling timing side channels and Denial of Service (DoS) attacks. This paper presents a methodology for evaluating the memory hierarchy of hardware platforms, focusing on timing interference and side-channel leakage. Using the OpenPiton platform, we identify and characterize a cross-core covert channel and demonstrate a proof-of-concept side-channel attack exploiting the Network-on-Chip (NoC). Additionally, we evaluate the impact of NoC contention on the worst-case execution time (WCET) of safety-critical applications. Despite exploring software-based mitigations, we find that covert channels cannot be completely eliminated without significant performance trade-offs.