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.
History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: kubernetes

Published: 2022-02-01T10:33:00.317144Z

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