As mitigations to a report from 2019 and CVE-2020-8555, Kubernetes attempts to prevent proxied connections from accessing link-local or localhost networks when making user-driven connections to Services, Pods, Nodes, or StorageClass service providers. As part of this mitigation Kubernetes does a DNS name resolution check and validates that response IPs are not in the link-local (169.254.0.0/16) or localhost (127.0.0.0/8) range. Kubernetes then performs a second DNS resolution without validation for the actual connection. If a non-standard DNS server returns different non-cached responses, a user may be able to bypass the proxy IP restriction and access private networks on the control plane.
Advisories
Source ID Title
EUVD EUVD EUVD-2022-1153 As mitigations to a report from 2019 and CVE-2020-8555, Kubernetes attempts to prevent proxied connections from accessing link-local or localhost networks when making user-driven connections to Services, Pods, Nodes, or StorageClass service providers. As part of this mitigation Kubernetes does a DNS name resolution check and validates that response IPs are not in the link-local (169.254.0.0/16) or localhost (127.0.0.0/8) range. Kubernetes then performs a second DNS resolution without validation for the actual connection. If a non-standard DNS server returns different non-cached responses, a user may be able to bypass the proxy IP restriction and access private networks on the control plane.
Github GHSA Github GHSA GHSA-qh36-44jv-c8xj Potential proxy IP restriction bypass in Kubernetes
Fixes

Solution

No solution given by the vendor.


Workaround

If this issue affects your clusters’ control planes, you can use dnsmasq for name resolution and configure the min-cache-ttl and neg-ttl parameters to a low non-zero value to enforce cached replies for proxied connections

History

Fri, 11 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00058}

epss

{'score': 0.00054}


cve-icon MITRE

Status: PUBLISHED

Assigner: kubernetes

Published:

Updated: 2024-09-16T17:08:37.065Z

Reserved: 2020-02-03T00:00:00

Link: CVE-2020-8562

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2022-02-01T11:15:10.903

Modified: 2024-11-21T05:39:02.180

Link: CVE-2020-8562

cve-icon Redhat

Severity : Low

Publid Date: 2021-05-04T00:00:00Z

Links: CVE-2020-8562 - Bugzilla

cve-icon OpenCVE Enrichment

No data.