Kubernetes on Insinuator.net - Bold Statements

CVE-2026-47237 – Overly Permissive Istio Permissions Allow Kubeflow Authorization Token Stealing

Wed, 20 May 2026 00:00:00 +0000

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.

KubeCon + CloudNativeCon Europe 2026

Wed, 01 Apr 2026 00:00:00 +0000

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.

Methodology for Assessing Kubernetes Namespace-Based Multi-Tenancy Setups

Thu, 26 Mar 2026 00:00:00 +0000

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.

Security Considerations on Istio’s CRDs with Namespace-based Multi-Tenancy

Wed, 25 Mar 2026 00:00:00 +0000

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).

In collaboration with Istio, we published a guest submission in Istio’s blog (as well as below), a Security Bulletin, and an update to their Security Model to address this issue.

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.

TROOPERS20 Training Teaser: Swim with the whales – Docker, DevOps & Security in Enterprise Environments

Mon, 02 Dec 2019 00:00:00 +0000

Containerization dominates the market nowadays. Fancy buzzwords like continuous integration/deployment/delivery, microservices, containers, DevOps are floating around, but what do they mean? What benefits do they offer compared to the old dogmas? You’re gonna find out in our training!

We are going to start with the basics of Docker, Containers and DevOps, but soon you’ll end up with your own applications running inside containers with the images residing in your own registry. Of course, following the microservices approach, and the second day hasn’t even started.After the fundamental topics of containerization are understood, you’re going to create and operate your own Kubernetes cluster. A lot of fun and challenging exercises lie ahead, to give you hands-on experience with all the technologies.

DevSecCon19 London – How to Secure OpenShift Environments and What Happens If You Don´t

Tue, 19 Nov 2019 00:00:00 +0000

This week I was at DevSecCon in London to present my current research on Red Hat OpenShift. In this talk, I gave a brief introduction to OpenShift, demonstrated some threats that exist for such environments, and dived into different configuration issues that may affect the security of OpenShift environments. The implications of misconfigurations of such an environment have been shown in live demos.

You can find the slides for my talk here.

Catching fire with Docker, DevOps & Security in Enterprise Environments

Fri, 04 Jan 2019 00:00:00 +0000

Docker has become the go-to technology in enterprise- and DevOps contexts. Yet, before mastering a skill, there is the thumb rule: one must learn the basics to have solid fundament before building a house on top.

Simon and I start from the very beginning. We introduce you to the fundamental concepts of containers starting at process isolation and extending our tour to the whole ecosystem of Docker and further associated technologies. We will cover Docker, microservices, containers, DevOps, continuous integration/deployment/delivery – all those fancy buzzwords that can be read in the context of modern software development methodologies.