REDHAT-BUG-2484720: High severity Tekton OpenShift Pipelines Operator (tektoncd/operator) vulnerability

A flaw was found in the OpenShift Pipelines operator (tektoncd/operator). The operator ships a ClusterRoleBinding (tekton-scheduler-rolebinding) that binds ClusterRole/tekton-scheduler-role to the system:authenticated group, granting all authenticated users cluster-wide create/update/patch/delete permissions on kueue.x-k8s.io resources (ResourceFlavor, Workload, WorkloadPriorityClass) and create/update permissions on cert-manager.io resources (Certificate, Issuer). When Kueue CRDs are present (e.g., via RHOAI), any authenticated user can disrupt cross-tenant workload scheduling by deleting ResourceFlavors, destroy other tenants' Workload objects, or tamper with scheduling priority. When cert-manager is installed, any authenticated user can create Certificate objects targeting arbitrary Secrets, including the default ingress controller's TLS Secret (openshift-ingress/router-certs-default), causing cert-manager to overwrite it with an attacker-influenced certificate. This confused deputy attack crosses authorization boundaries — the attacker cannot write Secrets directly but leverages cert-manager's ServiceAccount to do so. The RBAC objects are installed unconditionally even when the Tekton Scheduler feature is disabled.