Vulnerability in Kubernetes

CVE-2020-8561

A security issue was discovered in Kubernetes where actors that control the responses of MutatingWebhookConfiguration or ValidatingWebhookConfiguration requests are able to redirect kube-apiserver requests to private networks of the apiserver. If that user can view kube-apiserver logs when the log level is set to 10, they can view the redirected responses and headers in the logs.

EPSS: 0.021 (79.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:N/A:N.

Affected products

  • Kubernetes — versions 1.21.5, next of 1.21.5, next of 1.22.2

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-8561?
CVE-2020-8561 is a medium-severity vulnerability in Kubernetes, classified under Unintended Proxy or Intermediary (Confused Deputy). CVSS score: 4.1/10. Published 2021-09-20.
How severe is CVE-2020-8561?
Medium severity. CVSS v3 base score is 4.1 out of 10.
Is CVE-2020-8561 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.