CVE-2024-1725: Unauthorized Access to OpenShift Virtualization Hosted Control Plane Worker Node Volume through kubevirt-csi Flaw

A critical security vulnerability, tracked as CVE-2024-1725, has been identified in the kubevirt-csi component of OpenShift Virtualization's Hosted Control Plane (HCP). This flaw could allow an authenticated attacker to gain unauthorized access to the root HCP worker node's volume by creating a custom Persistent Volume that matches the name of a worker node.

Introduction

The OpenShift Virtualization technology stack is built upon the robust foundation provided by the Kubernetes container orchestration platform. It enables the deployment and management of virtual machines (VMs) alongside containers and serverless deployments, thereby offering a unified and simplified experience for developers and system administrators. The Hosted Control Plane (HCP) component in the OpenShift Virtualization ecosystem is responsible for managing the worker nodes that host virtual machine workloads.

Exploit Details

The vulnerability revolves around the kubevirt-csi (Container Storage Interface) component, which facilitates the provisioning, attaching, and mounting of Persistent Volumes (PVs) in a Kubernetes environment. The kubevirt-csi flaw allows an attacker to create a custom Persistent Volume that bears the same name as an existing worker node. Consequently, this would grant the attacker unauthorized access to the root HCP worker node's volume and all its associated data.

The following code snippet demonstrates a sample of how the exploit can potentially be executed

apiVersion: v1
kind: PersistentVolume
metadata:
  name: worker-node-XYZ
spec:
  capacity:
    storage: 1Gi
  volumeMode: Block
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  csi:
    driver: io.kubevirt.csi
    volumeHandle: kad976c8-b1b-11e8-9c22-6a00025550e
  mountOptions:
    - rw

With this exploit, threat actors can potentially tamper with the worker node's configurations, steal sensitive information, or even deploy malicious workloads, resulting in an elevated risk to the confidentiality, integrity, and availability of the affected HCP environment.

Original References

1. CVE Details: https://nvd.nist.gov/vuln/detail/CVE-2024-1725
2. OpenShift Virtualization Documentation: https://docs.openshift.com/container-platform/4.7/virt/about-virt.html
3. KubeVirt CSI: https://kubevirt.io/user-guide/operations/component_features/#csi

Mitigation

At the time of writing, there is no available fix for the vulnerability. However, it is highly recommended to monitor and restrict permissions for creating custom Persistent Volumes within a Kubernetes cluster, and ensure that only trusted and authorized users have access to such privileges.

Regularly updating the Kubernetes environment, associated components, and following security best practices laid out by the project's maintainers will help in maintaining a secure and robust infrastructure.

Conclusion

CVE-2024-1725 is a severe vulnerability within the kubevirt-csi component that affects OpenShift Virtualization's Hosted Control Plane. Continuous monitoring, updating, and applying security best practices can help mitigate the impacts of this flaw and ensure the safe operation of the affected systems.

Timeline

Published on: 03/07/2024 20:15:50 UTC
Last modified on: 04/26/2024 20:15:07 UTC