CVE-2026-71303

{
  "id": "CVE-2026-71303",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-18T20:17:23.403",
  "lastModified": "2026-10-22T22:10:00.250",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Lemur manages TLS certificate creation. Prior to 1.9.3, _validate_acme_url enforced ACME_DIRECTORY_HOST_ALLOWLIST when an authority was created, but PUT /api/1/authorities/ passed options to lemur/authorities/service.py without applying the same check. A user holding an authority role could replace the stored acme_url with an internal service or instance-metadata URL such as 169.254.169.254. The next issuance operation loaded that value and passed it to ClientV2.get_directory, causing an outbound request from the Lemur backend. This bypassed the creation-time mitigation for CVE-2026-55166 and could expose internal services or cloud metadata. The fix revalidates acme_url whenever authority options are updated. This issue is fixed in version 1.9.3."
    },
    {
      "lang": "es",
      "value": "Lemur gestiona la creación de certificados TLS. Antes de la versión 1.9.3, “_validate_acme_url” aplicaba ACME_DIRECTORY_HOST_ALLOWLIST cuando se creaba una autoridad, pero PUT /API/1/authorities/ pasaba opciones a lemur/authorities/service.py sin aplicar la misma comprobación. Un usuario con un rol de autoridad podía reemplazar la “acme_url” almacenada con un servicio interno o una URL de metadatos de instancia, como 169.254.169.254. La siguiente operación de emisión cargaba ese valor y lo pasaba a ClientV2.get_directory, causando una solicitud saliente desde el backend de Lemur. Esto eludía la mitigación en tiempo de creación para CVE-2026-55166 y podía exponer servicios internos o metadatos de la nube. La solución revalida la “acme_url” cada vez que se actualizan las opciones de autoridad. Este problema está corregido en la versión 1.9.3."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Netflix",
          "product": "lemur",
          "versions": [
            {
              "version": "< 1.9.3",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N",
          "baseScore": 7.7,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 4.0
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-18T19:45:59.586663Z",
          "id": "CVE-2026-71303",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/Netflix/lemur/commit/edca0390f930344d65ff4ca37a669c2320e3dfad",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/Netflix/lemur/releases/tag/v1.9.3",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/Netflix/lemur/security/advisories/GHSA-v5rc-cpwc-cfpr",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/Netflix/lemur/security/advisories/GHSA-v5rc-cpwc-cfpr",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}