CVE-2021-25736 (GCVE-0-2021-25736)

Vulnerability from cvelistv5 – Published: 2023-10-30 02:19 – Updated: 2025-06-12 14:42
VLAI
Title
Windows kube-proxy LoadBalancer contention
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.
Severity
5.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-06-12 14:39 UTC
CWE
Assigner
kubernetes CNA under the mitre root
CNA scorecard – unranked: 2 records in the last 180 days, 10 needed details
References
Impacted products
Vendor Product Version CPE status
Kubernetes Kubernetes Affected: 0 , ≤ v1.20.5 (v1.20.5)
guessed Create a notification for this product.
Credits
Eric Paris Christian Hernandez
Show details on NVD website
To clipboard 

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              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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          ],
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              "cvssV3_1": {
                "attackComplexity": "HIGH",
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      "cveMetadata": {
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        "cveId": "CVE-2021-25736",
        "datePublished": "2023-10-30T02:19:48.916Z",
        "dateReserved": "2021-01-21T21:42:58.237Z",
        "dateUpdated": "2025-06-12T14:42:12.231Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
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  }
}



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