{"id":"CVE-2021-25737","state":"PUBLISHED","title":"Holes in EndpointSlice Validation Enable Host Network Hijack","description":"A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node. Kubernetes already prevents creation of Endpoint IPs in the localhost or link-local range, but the same validation was not performed on EndpointSlice IPs.","publishedAt":"2021-09-06T11:32:01.989Z","updatedAt":"2024-09-16T21:04:34.209Z","severity":{"score":2.7,"label":"Low","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N","source":"kubernetes"},"assigner":"kubernetes","products":["Kubernetes Kubernetes"],"affected":[{"vendor":"Kubernetes","product":"Kubernetes","versions":[{"version":"unspecified","status":"affected","lessThanOrEqual":"1.18.18","versionType":"custom"},{"version":"unspecified","status":"affected","lessThanOrEqual":"1.19.10","versionType":"custom"},{"version":"unspecified","status":"affected","lessThanOrEqual":"1.20.6","versionType":"custom"},{"version":"unspecified","status":"affected","lessThanOrEqual":"1.21.0","versionType":"custom"}]}],"references":["https://groups.google.com/g/kubernetes-security-announce/c/xAiN3924thY","https://github.com/kubernetes/kubernetes/issues/102106","https://security.netapp.com/advisory/ntap-20211004-0004/"],"weaknesses":["CWE-184"],"ingestedAt":"2026-10-29T19:48:10.461Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2021/25xxx/CVE-2021-25737.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2021-25737","state":"PUBLISHED","datePublished":"2021-09-06T11:32:01.989Z","dateUpdated":"2024-09-16T21:04:34.209Z","assignerShortName":"kubernetes","assignerOrgId":"a6081bf6-c852-4425-ad4f-a67919267565","dateReserved":"2021-01-21T00:00:00.000Z"},"containers":{"cna":{"title":"Holes in EndpointSlice Validation Enable Host Network Hijack","descriptions":[{"lang":"en","value":"A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node. Kubernetes already prevents creation of Endpoint IPs in the localhost or link-local range, but the same validation was not performed on EndpointSlice IPs."}],"affected":[{"vendor":"Kubernetes","product":"Kubernetes","versions":[{"version":"unspecified","status":"affected","lessThanOrEqual":"1.18.18","versionType":"custom"},{"version":"unspecified","status":"affected","lessThanOrEqual":"1.19.10","versionType":"custom"},{"version":"unspecified","status":"affected","lessThanOrEqual":"1.20.6","versionType":"custom"},{"version":"unspecified","status":"affected","lessThanOrEqual":"1.21.0","versionType":"custom"}]}],"references":[{"url":"https://groups.google.com/g/kubernetes-security-announce/c/xAiN3924thY","tags":["x_refsource_MISC"]},{"url":"https://github.com/kubernetes/kubernetes/issues/102106","tags":["x_refsource_MISC"]},{"url":"https://security.netapp.com/advisory/ntap-20211004-0004/","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":2.7,"baseSeverity":"LOW","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-184","description":"CWE-184 Incomplete Blacklist","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"kubernetes","dateUpdated":"2021-10-04T18:06:22.000Z","orgId":"a6081bf6-c852-4425-ad4f-a67919267565"},"credits":[{"lang":"en","value":"John Howard"}],"datePublic":"2021-05-18T00:00:00.000Z","source":{"defect":["https://github.com/kubernetes/kubernetes/issues/102106"],"discovery":"EXTERNAL"},"x_generator":{"engine":"Vulnogram 0.0.9"},"x_legacyV4Record":{"CVE_data_meta":{"ASSIGNER":"security@kubernetes.io","DATE_PUBLIC":"2021-05-18T19:00:00.000Z","ID":"CVE-2021-25737","STATE":"PUBLIC","TITLE":"Holes in EndpointSlice Validation Enable Host Network Hijack"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"Kubernetes","version":{"version_data":[{"version_affected":"<=","version_value":"1.18.18"},{"version_affected":"<=","version_value":"1.19.10"},{"version_affected":"<=","version_value":"1.20.6"},{"version_affected":"<=","version_value":"1.21.0"}]}}]},"vendor_name":"Kubernetes"}]}},"credit":[{"lang":"eng","value":"John Howard"}],"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node. Kubernetes already prevents creation of Endpoint IPs in the localhost or link-local range, but the same validation was not performed on EndpointSlice IPs."}]},"generator":{"engine":"Vulnogram 0.0.9"},"impact":{"cvss":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":2.7,"baseSeverity":"LOW","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-184 Incomplete Blacklist"}]}]},"references":{"reference_data":[{"name":"https://groups.google.com/g/kubernetes-security-announce/c/xAiN3924thY","refsource":"MISC","url":"https://groups.google.com/g/kubernetes-security-announce/c/xAiN3924thY"},{"name":"https://github.com/kubernetes/kubernetes/issues/102106","refsource":"MISC","url":"https://github.com/kubernetes/kubernetes/issues/102106"},{"name":"https://security.netapp.com/advisory/ntap-20211004-0004/","refsource":"CONFIRM","url":"https://security.netapp.com/advisory/ntap-20211004-0004/"}]},"source":{"defect":["https://github.com/kubernetes/kubernetes/issues/102106"],"discovery":"EXTERNAL"}}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://groups.google.com/g/kubernetes-security-announce/c/xAiN3924thY","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://github.com/kubernetes/kubernetes/issues/102106","tags":["x_refsource_MISC","x_transferred"]},{"url":"https://security.netapp.com/advisory/ntap-20211004-0004/","tags":["x_refsource_CONFIRM","x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-03T20:11:27.584Z"}}]}}}