CVE-2020-8562: kubernetes

Vulnerability summary

CVE-2020-8562 is a low (CVSS 3.5) vulnerability in kubernetes. EPSS estimates a 1.08% chance of exploitation in the next 30 days, higher than 64.6% of scored vulnerabilities.

Timeline

1. 01-02-2022
   PublishedVulnerability first disclosed.
2. 01-06-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-367Time-of-check Time-of-use (TOCTOU) Race ConditionThe product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.