{"containers":{"cna":{"affected":[{"product":"Kubernetes","vendor":"Kubernetes","versions":[{"lessThan":"*","status":"affected","version":"0","versionType":"semver"}]}],"credits":[{"lang":"en","value":"Javier Provecho"}],"datePublic":"2021-05-04T00:00:00.000Z","descriptions":[{"lang":"en","value":"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."}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":2.2,"baseSeverity":"LOW","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-367","description":"CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition","lang":"en","type":"CWE"}]}],"providerMetadata":{"orgId":"a6081bf6-c852-4425-ad4f-a67919267565","shortName":"kubernetes","dateUpdated":"2026-06-01T21:45:40.339Z"},"references":[{"tags":["x_refsource_MISC"],"url":"https://kubernetes.io/blog/2026/05/26/reconciling-unfixed-kubernetes-cves/"},{"tags":["x_refsource_MISC"],"url":"https://github.com/kubernetes/kubernetes/issues/101493"},{"tags":["x_refsource_MISC"],"url":"https://groups.google.com/g/kubernetes-security-announce/c/-MFX60_wdOY"},{"tags":["x_refsource_CONFIRM"],"url":"https://security.netapp.com/advisory/ntap-20220225-0002/"}],"source":{"defect":["https://github.com/kubernetes/kubernetes/issues/101493"],"discovery":"EXTERNAL"},"title":"Bypass of Kubernetes API Server proxy TOCTOU","workarounds":[{"lang":"en","value":"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"}],"x_generator":{"engine":"Vulnogram 0.0.9"}},"adp":[{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-04T10:03:46.172Z"},"title":"CVE Program Container","references":[{"tags":["x_refsource_MISC","x_transferred"],"url":"https://github.com/kubernetes/kubernetes/issues/101493"},{"tags":["x_refsource_MISC","x_transferred"],"url":"https://groups.google.com/g/kubernetes-security-announce/c/-MFX60_wdOY"},{"tags":["x_refsource_CONFIRM","x_transferred"],"url":"https://security.netapp.com/advisory/ntap-20220225-0002/"}]}]},"cveMetadata":{"assignerOrgId":"a6081bf6-c852-4425-ad4f-a67919267565","assignerShortName":"kubernetes","cveId":"CVE-2020-8562","datePublished":"2022-02-01T10:33:00.317Z","dateReserved":"2020-02-03T00:00:00.000Z","dateUpdated":"2026-06-01T21:45:40.339Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"}