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oesa-2021-1373
Vulnerability from osv_openeuler
Published
2021-09-30 11:04
Modified
2026-08-06 11:04
Summary
kubernetes security update
Details

Container cluster management.

Security Fix(es):

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.(CVE-2021-25737)

A security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission Webhook for Nodes that denies admission based at least partially on the old state of the Node object. Validating Admission Webhook does not observe some previous fields.(CVE-2021-25735)


{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "kubernetes-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-kubelet-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-client-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-node-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-master-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-help-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-kubeadm-1.20.2-5.oe1.aarch64.rpm"
        ],
        "src": [
          "kubernetes-1.20.2-5.oe1.src.rpm"
        ],
        "x86_64": [
          "kubernetes-kubeadm-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-client-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-master-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-node-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-help-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-kubelet-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-1.20.2-5.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP1",
        "name": "kubernetes",
        "purl": "pkg:rpm/openEuler/kubernetes\u0026distro=openEuler-20.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.20.2-5.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "kubernetes-kubeadm-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-kubelet-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-client-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-node-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-help-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-master-1.20.2-5.oe1.aarch64.rpm",
          "kubernetes-1.20.2-5.oe1.aarch64.rpm"
        ],
        "src": [
          "kubernetes-1.20.2-5.oe1.src.rpm"
        ],
        "x86_64": [
          "kubernetes-help-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-kubelet-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-master-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-kubeadm-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-node-1.20.2-5.oe1.x86_64.rpm",
          "kubernetes-client-1.20.2-5.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP2",
        "name": "kubernetes",
        "purl": "pkg:rpm/openEuler/kubernetes\u0026distro=openEuler-20.03-LTS-SP2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.20.2-5.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Medium"
  },
  "details": "Container cluster management.\r\n\r\nSecurity Fix(es):\r\n\r\nA 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.(CVE-2021-25737)\r\n\r\nA security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission Webhook for Nodes that denies admission based at least partially on the old state of the Node object. Validating Admission Webhook does not observe some previous fields.(CVE-2021-25735)",
  "id": "OESA-2021-1373",
  "modified": "2026-08-06T11:04:38Z",
  "published": "2021-09-30T11:04:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2021-1373"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-25737"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-25735"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "kubernetes security update",
  "upstream": [
    "CVE-2021-25737",
    "CVE-2021-25735"
  ]
}



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