CVE-2026-66788 Lighthouse: lighthouse: arbitrary namespace injection via attacker-controlled broker label
Remote attackers can inject unauthorized resources into any namespace, including system ones, by exploiting attacker-controlled labels in Lighthouse.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-66788?
CVE-2026-66788 is a critical missing authorization vulnerability in Red Hat Advanced Cluster Management for Kubernetes 2.16, published on 20 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in Lighthouse. A remote attacker, by compromising a spoke cluster, can exploit a vulnerability where the destination namespace for resource injection is derived from an attacker-controlled label or annotation on the broker object. This allows the attacker to inject unauthorized EndpointSlices and ServiceImports into any namespace on peer clusters, including critical system namespaces like kube-system and openshift-*. This could lead to privilege escalation or other forms of system compromise within the cluster.
Weakness: CWE-1104
Which versions are affected by CVE-2026-66788?
How do I fix CVE-2026-66788?
No fix has been published for CVE-2026-66788 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-66788 being exploited?
There is no known exploitation of CVE-2026-66788 in the wild and no public exploit code.
Sources
Also known as GHSA-264j-8377-4hmm.