CVE-2020-8562 — kubernetes
LOWCVE-2020-8562 is a low-severity (CVSS 3.1) CWE-367 vulnerability in k8s.io/kubernetes. No vendor fix is recorded yet; mitigation options are listed below.
Potential proxy IP restriction bypass in Kubernetes
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2020-8562 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 386,684 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
k8s.io/kubernetes🐹k8s.io/kubernetes🐹k8s.io/kubernetes🐹k8s.io/kubernetesReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
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. All versions of Kubernetes are impacted, and there is no fix in place.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | k8s.io/kubernetes | ≥ 1.21.0 | No fix |
| 🐹Go | k8s.io/kubernetes | ≥ 1.20.0 | No fix |
| 🐹Go | k8s.io/kubernetes | ≥ 1.19.0 | No fix |
| 🐹Go | k8s.io/kubernetes | all versions | No fix |
Affected Products
kuberneteskubernetesDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for k8s.io/kubernetes, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of k8s.io/kubernetes has shipped for CVE-2020-8562 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2020-8562 in your dependencies?
Find it across Go, including transitive dependencies.