CVE-2026-17527 Red Hat CVE debrief

Who should care

Users and service accounts bound to the cdi.kubevirt.io:view ClusterRole, especially those with cluster-wide ClusterRoleBinding, and administrators of Kubernetes clusters using CDI, should be aware of this vulnerability and take necessary precautions to mitigate its impact.

Technical summary

The aggregated cdi.kubevirt.io:view ClusterRole in CDI includes a rule granting create on the datavolumes/source subresource. This allows a user or service account with the view role and write access to any single namespace to exfiltrate PVC contents across namespaces, bypassing isolation and the role's read-only guarantee. The vulnerability affects users and service accounts bound to the cdi.kubevirt.io:view ClusterRole, especially those with cluster-wide ClusterRoleBinding, and administrators of Kubernetes clusters using CDI.

Defensive priority

High priority for users and administrators of Kubernetes clusters using CDI, especially those with ClusterRoleBindings for the view role, to review and restrict access, monitor for suspicious activities, and apply vendor remediation when available.

Recommended defensive actions

• Review and restrict ClusterRoleBindings for the cdi.kubevirt.io:view role.
• Limit write access to namespaces for users and service accounts bound to the view role.
• Monitor for unusual PVC access patterns.
• Implement compensating controls for sensitive data.
• Apply vendor remediation when available.
• Perform regular security audits to detect and address potential vulnerabilities.
• Enhance monitoring and logging to detect suspicious activities related to PVC access.

Evidence notes

Evidence is based on limited information from NVD and Red Hat sources. Further investigation is recommended to fully understand the vulnerability's impact and affected systems. The vulnerability allows unauthorized data exfiltration via the aggregated cdi.kubevirt.io:view ClusterRole. CDI's DataVolume clone authorization accepts this permission as sufficient to authorize cloning the contents of any PVC the caller can name, without requiring write access to the source namespace. A user or service account bound to the view role, commonly granted cluster-wide via ClusterRoleBinding, who also has ordinary write access (edit/admin) to any single namespace, can use this to exfiltrate the contents of any PVC in the cluster into a namespace they control, bypassing namespace isolation and the read-only guarantee of the view role.

Official resources