cve-2021-25736
Vulnerability from cvelistv5
Published
2023-10-30 02:19
Modified
2025-02-13 16:27
Severity ?
5.8 (Medium) - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N
Summary
Kube-proxy on Windows can unintentionally forward traffic to local processes listening on the same port (“spec.ports[*].port”) as a LoadBalancer Service when the LoadBalancer controller does not set the “status.loadBalancer.ingress[].ip” field. Clusters where the LoadBalancer controller sets the “status.loadBalancer.ingress[].ip” field are unaffected.
References
jordan@liggitt.nethttps://github.com/kubernetes/kubernetes/pull/99958Third Party Advisory
jordan@liggitt.nethttps://groups.google.com/g/kubernetes-security-announce/c/lIoOPObO51Q/m/O15LOazPAgAJMailing List, Third Party Advisory
jordan@liggitt.nethttps://security.netapp.com/advisory/ntap-20231221-0003/
af854a3a-2127-422b-91ae-364da2661108https://github.com/kubernetes/kubernetes/pull/99958Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://groups.google.com/g/kubernetes-security-announce/c/lIoOPObO51Q/m/O15LOazPAgAJMailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20231221-0003/
Impacted products
Vendor Product Version
Kubernetes Kubernetes Version: 0
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{
   containers: {
      adp: [
         {
            providerMetadata: {
               dateUpdated: "2024-08-03T20:11:28.044Z",
               orgId: "af854a3a-2127-422b-91ae-364da2661108",
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                  url: "https://groups.google.com/g/kubernetes-security-announce/c/lIoOPObO51Q/m/O15LOazPAgAJ",
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               {
                  tags: [
                     "x_transferred",
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                  url: "https://security.netapp.com/advisory/ntap-20231221-0003/",
               },
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            title: "CVE Program Container",
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      cna: {
         affected: [
            {
               defaultStatus: "unaffected",
               modules: [
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               ],
               platforms: [
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               ],
               product: "Kubernetes",
               repo: "https://github.com/kubernetes/kubernetes",
               vendor: "Kubernetes",
               versions: [
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                     status: "affected",
                     version: "0",
                     versionType: "v1.20.5",
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         ],
         credits: [
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               type: "finder",
               user: "00000000-0000-4000-9000-000000000000",
               value: "Eric Paris",
            },
            {
               lang: "en",
               type: "finder",
               user: "00000000-0000-4000-9000-000000000000",
               value: "Christian Hernandez",
            },
         ],
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                  attackVector: "NETWORK",
                  availabilityImpact: "NONE",
                  baseScore: 5.8,
                  baseSeverity: "MEDIUM",
                  confidentialityImpact: "HIGH",
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                  scope: "CHANGED",
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            },
         ],
         source: {
            discovery: "UNKNOWN",
         },
         title: "Windows kube-proxy LoadBalancer contention",
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   },
   cveMetadata: {
      assignerOrgId: "a6081bf6-c852-4425-ad4f-a67919267565",
      assignerShortName: "kubernetes",
      cveId: "CVE-2021-25736",
      datePublished: "2023-10-30T02:19:48.916Z",
      dateReserved: "2021-01-21T21:42:58.237Z",
      dateUpdated: "2025-02-13T16:27:50.253Z",
      state: "PUBLISHED",
   },
   dataType: "CVE_RECORD",
   dataVersion: "5.1",
   "vulnerability-lookup:meta": {
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   },
}


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