In fully managed serverless environments, cloud service providers handle the underlying infrastructure, reducing application developers’ operational and maintenance efforts. However, these environments limit the use of traditional cybersecurity frameworks and tools, compromising observability and situational awareness capabilities for security tasks (e.g., risk assessment, incident response). Additionally, existing security frameworks for serverless applications often lack generalizability across architectures and require specialized expertise. In this paper, we propose a three-layer security stack for fully managed serverless applications. The first layer establishes a foundational generic ontology that models serverless application resources and their interactions using API logs. In the second layer, the ontology is leveraged via perimeterless pipeline, to map the logs into a unified application activity KG, and in the third layer, two situational awareness tools that utilize the graph-based representation are implemented: (1) an incident response dashboard that leverages the ontology to visualize and examine application activity logs in the context of cybersecurity alerts; our user study showed that this dashboard enabled participants to respond 10% more accurately and almost twice as fast than the examined baseline tool, and (2) a criticality of asset (CoA) risk assessment framework that enables efficient expert-based prioritization in cybersecurity contexts; our expert-based questionnaire demonstrated strong agreement, achieving a Kendall-W score of 0.7179.

The O-RAN ALLIANCE is defining architectures, interfaces, operations, and security requirements for cellular networks based on Open Radio Access Network (RAN) principles. In this context, O-RAN introduced the RAN Intelligent Controllers (RICs) to enable dynamic control of cellular networks via data-driven applications referred to as rApps and xApps. RICs enable for the first time truly intelligent and self-organizing cellular networks. However, enabling the execution of many Artificial Intelligence (AI) algorithms making autonomous control decisions to fulfill diverse (and possibly conflicting) goals poses unprecedented challenges. For instance, the execution of one xApp aiming at maximizing throughput and one aiming at minimizing energy consumption would inevitably result in diametrically opposed resource allocation strategies. Therefore, conflict management becomes a crucial component of any functional intelligent O-RAN system. This article studies the problem of conflict mitigation in O-RAN and proposes PACIFISTA, a framework to detect, characterize, and mitigate conflicts generated by O-RAN applications that control RAN parameters. PACIFISTA leverages a profiling pipeline to tests O-RAN applications in a sandbox environment, and combines hierarchical graphs with statistical models to detect the existence of conflicts and evaluate their severity. Experiments on Colosseum and OpenRAN Gym demonstrate PACIFISTA's ability to predict conflicts and provide valuable information before potentially conflicting xApps are deployed in production systems. We use PACIFISTA to demonstrate that users can experience a 16% throughput loss even in the case of xApps with similar goals, and that applications with conflicting goals might cause severe instability and result in up to 30% performance degradation. We also show that PACIFISTA can help operators to identify conflicting applications and maintain performance degradation below a tolerable threshold.