CVE-2026-52723

{
  "id": "CVE-2026-52723",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-18T17:16:59.200",
  "lastModified": "2026-10-22T22:10:00.250",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "ePA 3.x Integration implements the authorization workflow and writes Medical Information Objects to Germany's electronic patient record. Prior to 1.3.0, ePA 3.x Integration performs VAU server certificate validation in app/vau/VAUProtokoll.py without anchoring the signed_vau_server_pub_keys and AUT_VAU_CertData certificate path to independent trusted material. A network-positioned attacker between the DiGA backend and the ePA system can intercept the VAU handshake, supply attacker-controlled certificate and key material, and satisfy the circular trust relationship. Because TLS certificate verification is also disabled in affected versions, no independent server-authentication layer prevents the attack. The attacker can impersonate the VAU server, control the negotiated session keys, and read or modify all encrypted VAU traffic. This issue is fixed in version 1.3.0."
    },
    {
      "lang": "es",
      "value": "La Integración de ePA 3.x implementa el flujo de trabajo de autorización y escribe Objetos de Información Médica en el historial electrónico del paciente de Alemania. Antes de la versión 1.3.0, la Integración de ePA 3.x realiza la validación del certificado del servidor VAU en app/vau/VAUProtokoll.py sin anclar la ruta del certificado signed_vau_server_pub_keys y AUT_VAU_CertData a material de confianza independiente. Un atacante posicionado en la red entre el backend de DiGA y el sistema ePA puede interceptar el handshake VAU, suministrar material de certificado y clave controlado por el atacante, y satisfacer la relación de confianza circular. Debido a que la verificación del certificado TLS también está deshabilitada en las versiones afectadas, ninguna capa independiente de autenticación del servidor previene el ataque. El atacante puede suplantar al servidor VAU, controlar las claves de sesión negociadas y leer o modificar todo el tráfico VAU cifrado. Este problema está solucionado en la versión 1.3.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "fbeta-GmbH",
          "product": "ePA3-Service-OpenSource",
          "versions": [
            {
              "version": "< 1.3.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
          "baseScore": 9.1,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-18T17:38:28.386866Z",
          "id": "CVE-2026-52723",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-295"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/fbeta-GmbH/ePA3-Service-OpenSource/commit/197c8c7fc41675f19c7f448696a2bc63fab9db5b",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/fbeta-GmbH/ePA3-Service-OpenSource/pull/12",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/fbeta-GmbH/ePA3-Service-OpenSource/releases/tag/1.3.0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/fbeta-GmbH/ePA3-Service-OpenSource/security/advisories/GHSA-q2jw-6c4w-86jc",
      "source": "[email protected]"
    },
    {
      "url": "https://www.machinespirits.de/advisory/a1da93",
      "source": "[email protected]"
    }
  ]
}