CVE-2026-10840: Openshift-pipelines-operator-rh: openshift-pipelines-operator: tekton-scheduler-rolebinding grants system:authenticated write access to kueue and cert-manager resources
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.
Other sources
A flaw was found in the OpenShift Pipelines operator. The tekton-scheduler-rolebinding ClusterRoleBinding grants the system:authenticated group write access to Kueue and cert-manager custom resources via the tekton-scheduler-role ClusterRole. When Kueue or cert-manager CRDs are present on the cluster, any authenticated user can disrupt workload scheduling, tamper with scheduling priorities, delete other tenants' Workload objects, or induce cert-manager to overwrite TLS Secrets including the default ingress controller certificate.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Configuration
Restrict/adjust the ClusterRoleBinding named "tekton-scheduler-rolebinding" so it does not grant the "system:authenticated" group 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).
OpenShift Pipelines operator (tektoncd/operator) ClusterRoleBinding tekton-scheduler-rolebinding (binds tekton-scheduler-role to system:authenticated) = Remove or restrict binding so system:authenticated does not have write access
Event History
Frequently Asked Questions
What is the severity of CVE-2026-10840?
CVE-2026-10840 has a critical severity score of 9.6.
How do I fix CVE-2026-10840?
To fix CVE-2026-10840, modify the tekton-scheduler-rolebinding to limit access and avoid binding to the system:authenticated group.
What impact does CVE-2026-10840 have on my OpenShift environment?
CVE-2026-10840 allows all authenticated users to create, update, patch, or delete resources in kueue and cert-manager, which poses a security risk.
Which software is affected by CVE-2026-10840?
CVE-2026-10840 affects the Red Hat OpenShift Pipelines operator.
When was CVE-2026-10840 published?
CVE-2026-10840 was published on June 4, 2026.