github - ghsa-w7r3-mgwf-4mqq

GHSA-W7R3-MGWF-4MQQ

Vulnerability from github – Published: 2025-09-17 00:31 – Updated: 2025-11-05 20:44

Summary

Kubernetes C# client accepts certificates from any CA without properly verifying the trust chain

Details

A vulnerability exists in the Kubernetes C# client where the certificate validation logic accepts properly constructed certificates from any Certificate Authority (CA) without properly verifying the trust chain. This flaw allows a malicious actor to present a forged certificate and potentially intercept or manipulate communication with the Kubernetes API server, leading to possible man-in-the-middle attacks and API impersonation.

Severity ?

6.8 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

Show details on source website

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "NuGet",
        "name": "KubernetesClient"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "17.0.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-9708"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-09-17T19:07:53Z",
    "nvd_published_at": "2025-09-16T22:15:33Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability exists in the Kubernetes C# client where the certificate validation logic accepts properly constructed certificates from any Certificate Authority (CA) without properly verifying the trust chain. This flaw allows a malicious actor to present a forged certificate and potentially intercept or manipulate communication with the Kubernetes API server, leading to possible man-in-the-middle attacks and API impersonation.",
  "id": "GHSA-w7r3-mgwf-4mqq",
  "modified": "2025-11-05T20:44:42Z",
  "published": "2025-09-17T00:31:11Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-9708"
    },
    {
      "type": "WEB",
      "url": "https://github.com/kubernetes/kubernetes/issues/134063"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/kubernetes-client/csharp"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/kubernetes-security-announce/c/rLopt2Msvbw/m/rK6XeNw2CgAJ"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2025/09/16/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Kubernetes C# client accepts certificates from any CA without properly verifying the trust chain"
}

CVE-2025-9708 (GCVE-0-2025-9708)

Vulnerability from cvelistv5 – Published: 2025-09-16 21:08 – Updated: 2025-11-04 21:15

Summary

Severity ?

6.8 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

CWE

CWE-295 - Improper Certificate Validation

Assigner

kubernetes

References

URL

Tags

	https://groups.google.com/g/kubernetes-security-a…	mailing-list
	https://github.com/kubernetes/kubernetes/issues/134063	issue-tracking

Impacted products

	Vendor	Product	Version
	Kubernetes	Kubernetes CSharp Client	Affected: 0 , ≤ 17.0.13 (semver) Unaffected: 17.0.14

Credits

elliott-beach

Show details on NVD website

JSON

To clipboard

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                  },
                  {
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                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-09-17T13:42:50.384978Z",
                "version": "2.0.3"
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      "metrics": [
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            "confidentialityImpact": "HIGH",
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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-W7R3-MGWF-4MQQ

CVE-2025-9708 (GCVE-0-2025-9708)

Tags

Sightings

Nomenclature