Quick answers
- Is CVE-2020-8554 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2020-8554 being exploited in the wild.
- How severe is CVE-2020-8554?
- Medium severity, with a CVSS score of 5, published 8 February 2022.
- Which products and versions are affected?
- k8s.io/kubernetes (Go) <= 1.22.0, SEMVER:introduced=0,last_affected=1.22.0; Kubernetes <= 1.22.0.
- Is there a fix for CVE-2020-8554?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2020-8554 attacked?
- It is attacked over the network, in an operating system.
- Am I affected by CVE-2020-8554?
- Check whether you run k8s.io/kubernetes (Go) or Kubernetes at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A design flaw in the Kubernetes API server allows for man-in-the-middle (MitM) attacks via unverified ownership of IP addresses. An attacker with permissions to create or edit Services and Pods can set the 'spec.externalIPs' field in a ClusterIP service to a target IP, causing the cluster to route traffic for that IP to the attacker's service. Additionally, if an attacker has the highly privileged permission to patch the 'status' of a LoadBalancer service, they can achieve a similar effect by modifying 'status.loadBalancer.ingress.ip'. This is a fundamental architectural issue with no direct code patch; mitigation requires using admission controllers (like the externalip-webhook) to restrict or allowlist the use of ExternalIPs.
Affected products
- Kubernetes Kubernetes <= 1.22.0
Identifiers
- CVE-2020-8554
- GHSA-j9wf-vvm6-4r9w
Timeline
- 2020-12-04: disclosed: Issue first opened on GitHub
- 2021-01-21: advisory: NVD publication date
- 2022-02-08: advisory: GitHub Advisory published
References
- https://github.com/kubernetes/kubernetes/issues/97076
- https://github.com/kubernetes/kubernetes/issues/97110
- https://groups.google.com/g/kubernetes-security-announce/c/iZWsF9nbKE8
- https://lists.apache.org/thread.html/r0c76b3d0be348f788cd947054141de0229af00c540564711e828fd40@%3Ccommits.druid.apache.org%3E
- https://lists.apache.org/thread.html/r1975078e44d96f2a199aa90aa874b57a202eaf7f25f2fde6d1c44942@%3Ccommits.druid.apache.org%3E