CVE-2020-8561 (GCVE-0-2020-8561)
Vulnerability from cvelistv5 – Published: 2021-09-20 17:05 – Updated: 2026-06-01 21:45
VLAI
EPSS
VEX
Title
Webhook redirect in kube-apiserver
Summary
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.
Severity
4.1 (Medium)
CWE
- CWE-441 - Unintended Proxy or Intermediary
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://kubernetes.io/blog/2026/05/26/reconciling… | x_refsource_MISC |
| https://groups.google.com/g/kubernetes-security-a… | x_refsource_MISC |
| https://github.com/kubernetes/kubernetes/issues/104720 | x_refsource_MISC |
| https://security.netapp.com/advisory/ntap-2021101… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Kubernetes | Kubernetes |
Affected:
0 , < *
(semver)
|
guessed |
Date Public
2021-09-15 00:00
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
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