fkie_cve-2025-66491
Vulnerability from fkie_nvd
Published
2025-12-09 01:16
Modified
2025-12-09 18:37
Severity ?
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
Traefik is an HTTP reverse proxy and load balancer. Versions 3.5.0 through 3.6.2 have inverted TLS verification logic in the nginx.ingress.kubernetes.io/proxy-ssl-verify annotation. Setting the annotation to "on" (intending to enable backend TLS certificate verification) actually disables verification, allowing man-in-the-middle attacks against HTTPS backends when operators believe they are protected. This issue is fixed in version 3.6.3.
References
security-advisories@github.comhttps://github.com/traefik/traefik/commit/14a1aedf5704673d875d210d7bacf103a43c77e4
security-advisories@github.comhttps://github.com/traefik/traefik/releases/tag/v3.6.3
security-advisories@github.comhttps://github.com/traefik/traefik/security/advisories/GHSA-7vww-mvcr-x6vj
Impacted products
Vendor Product Version


To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Traefik is an HTTP reverse proxy and load balancer. Versions 3.5.0 through 3.6.2 have inverted TLS verification logic in the nginx.ingress.kubernetes.io/proxy-ssl-verify annotation. Setting the annotation to \"on\" (intending to enable backend TLS certificate verification) actually disables verification, allowing man-in-the-middle attacks against HTTPS backends when operators believe they are protected. This issue is fixed in version 3.6.3."
    }
  ],
  "id": "CVE-2025-66491",
  "lastModified": "2025-12-09T18:37:13.640",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2025-12-09T01:16:55.720",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/traefik/traefik/commit/14a1aedf5704673d875d210d7bacf103a43c77e4"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/traefik/traefik/releases/tag/v3.6.3"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/traefik/traefik/security/advisories/GHSA-7vww-mvcr-x6vj"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-295"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}


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