GHSA-mw9r-p8xp-wx96 Strimzi: Cross-namespace privilege escalation via `Kafka.spec.entityOperator`

• Maven io.strimzi:strimzi: < 1.0.1 → fixed in 1.0.1

Impact Having the Topic and User operators to watch different namespaces than the one where the Kafka cluster is deployed, is a fully documented feature. When the `watchedNamespace` field is used within the Topic or User operator (as part of the `Kafka.spec.entityOperator` field), the Cluster Operator creates a Role granting full CRUD on Secrets into the specified namespace. It also creates a RoleBinding to bind such Role to the entity operator ServiceAccount within the namespace where the Kafka cluster runs. An attacker can craft a Kafka custom resource (in an attacker's namespace) with the `watchedNamespace` field set to a target namespace and then they can mint a token for the ServiceAccount (in the attacker's namespace) to read/write Secrets in that target. This is valid with any target namespace for which the Cluster Operator has the rights (regardless the value of the `STRIMZI_NAMESPACE` environment variable). The at-risk target namespaces are the namespaces which the user has given permissions to the Cluster Operator for, by creating related RoleBinding(s). Patches The issue is fixed in Strimzi 1.0.1 and 1.1.0 by adding a control to enable the watched namespace feature through a dedicated environment variable within the Cluster Operator deployment. The watched namespaces feature is disabled by default. Workarounds A possible workaround for this issue is about using a policy agent like Kyverno or OPA to prevent the usage of the `watchedNamespace` at configuration level within the `Kafka` custom resource.