Kubeflow is vulnerable to the theft of authorization tokens by any user of the
Kubeflow UI or APIs, such as the Dashboard, Pipelines API, or Notebooks. With
this token, the attacker can take over the user’s account and the data that is
processed by that user. The attacker needs a valid user with the kubeflow-edit
or Contributor role in a random Kubeflow namespace to perform this attack. This
is given if Automatic Profile Creation is enabled. A setup based on the
official manifests prior to version 1.10, and on most other packaged Kubeflow
distributions, is vulnerable.
The Istio edit permissions were removed by Kubeflow in a timely manner. Affected
users should update to the latest version to mitigate this issue.
Exactly one week ago, Sven and I had the incredible opportunity to give our very
first talk at KubeCon + CloudNativeCon
2026: How To Break Multi-Tenancy Again and Again …and What We Can Learn From It.
We discussed the challenges of namespace-based multi-tenancy and presented
real-world exploits in
Kubeflow, Istio,
and Traefik that bypass threat boundaries between namespaces and workloads.
Based on these problems, we developed a methodology to assess and address them.
You can find the methodology discussed in the talk in
detail in another blog post or
on GitHub. You can also find the
slides here.
This page introduces our structured methodology for assessing security risks in
Kubernetes environments that use Namespace-based Multi-Tenancy. It addresses
weaknesses that break Namespace-based isolation that not well studied, yet. We
found this issues during our research and presented them together with this
methodology in our
Talk at KubeCon + CloudNativeCon Europe 2026.
The methodology assumes that industry best practices, such as NetworkPolicies,
Role-Based Access Control (RBAC), and Pod Security Standards, are already in
place. These measures provide a necessary baseline level of protection against
well-known isolation threats. However, they are insufficient to address a class
of more subtle attack vectors arising from interactions between tenants and
shared components. Such attack vectors may still compromise the confidentiality,
integrity, and availability (CIA) of the cluster and its workloads, even in
well-hardened environments.
We reported a possible Man-in-the-Middle (MitM) attack scenario in which
a VirtualService can redirect or intercept traffic within the service mesh.
This affects Namespace-based Multi-Tenancy clusters where tenants have the
permissions to deploy Istio resources (networking.istio.io/v1).
This blog post highlights the risks of using Istio in multi-tenant clusters and
explains how users can mitigate these risks and safely operate Istio in their
deployments.
During a customer project, we identified privilege escalation vulnerabilities in
Broadcom VMware Aria Operations. It is possible to escalate the privileges of an
administrative vCenter user to an Aria administrator and take over systems
integrated in Aria. Meaning, the vCenter user can gain privileged access to
systems they have no access to. While both users might sound similarly
privileged, this is not true in most environments – especially not in complex
corporate environments: An insignificant vCenter user in a development
environment can take over all other vCenters in a complex corporate environment.