Securing production Kubernetes clusters is a critical and increasingly complex task. The decentralized and fragmented nature of security policies, such as Role-Based Access Control (RBAC) and NetworkPolicy resources, creates a significant semantic gap between high level security requirements and the low level reality of the cluster configuration. Manual verification is cognitively demanding, error prone, and does not scale, while existing automated tools are often siloed within a single domain, leaving blind spots at the intersection of authorization and network reachability. To bridge this gap, this thesis introduces a query-based verification approach that assesses cross-domain security properties, specifically across RBAC and NetworkPolicy, through a unified cluster model.