[Security Advisory] CVE-2023-5528: Insufficient input sanitization in in-tree storage plugin leads to privilege escalation on Windows nodes
Craig Ingram
Hello Kubernetes Community,
A security issue was discovered in Kubernetes where a user that can create pods and persistent volumes on Windows nodes may be able to escalate to admin privileges on those nodes. Kubernetes clusters are only affected if they are using an in-tree storage plugin for Windows nodes.
This issue has been rated High (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H), and assigned CVE-2023-5528.
Am I vulnerable?
Any kubernetes environment with Windows nodes is impacted. Run kubectl get nodes -l kubernetes.io/os=windows to see if any Windows nodes are in use.
Affected Versions
- kubelet >= v1.8.0 (including all later minor versions)
How do I mitigate this vulnerability?
The provided patch fully mitigates the vulnerability.
Outside of applying the patch, there are no known mitigations to this vulnerability.
Fixed Versions
- kubelet v1.28.4
- kubelet v1.27.8
- kubelet v1.26.11
- kubelet v1.25.16
These releases will be published over the course of today, November 14, 2023.
To upgrade, refer to the documentation:
https://kubernetes.io/docs/tasks/administer-cluster/cluster-management/#upgrading-a-cluster
Detection
Kubernetes audit logs can be used to detect if this vulnerability is being exploited. Persistent Volume create events with local path fields containing special characters are a strong indication of exploitation.
If you find evidence that this vulnerability has been exploited, please contact secu...@kubernetes.io
Additional Details
See the GitHub issue for more details: https://github.com/kubernetes/kubernetes/issues/121879
Acknowledgements
This vulnerability was reported by Tomer Peled @tomerpeled92
The issue was fixed and coordinated by the fix team:
James Sturtevant @jsturtevant
Mark Rossetti @marosset
Michelle Au @msau42
Jan Šafránek @jsafrane
Mo Khan @enj
Rita Zhang @ritazh
Micah Hausler @micahhausler
Sri Saran Balaji @SaranBalaji90
Craig Ingram @cji
and release managers:
Jeremy Rickard @jeremyrickard
Marko Mudrinić @xmudrii
Thank You,
Craig Ingram on behalf of the Kubernetes Security Response Committee