CVE-2026-11405

{
  "id": "CVE-2026-11405",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-06T20:16:29.450",
  "lastModified": "2026-10-25T20:10:00.147",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The web server binary /bin/httpd contains a hidden backdoor authentication mechanism in the login() function at 004c88b8.\r\n\r\n- The function contains a normal authentication path using MD5/hash-based password verification (prod_encode64/PasswordToMd5/check_rand_key).\r\n- After normal authentication fails, it calls GetValue(\"sys.rzadmin.password\") to read a backdoor password from the device configuration.\r\n- It performs a direct strcmp() comparison (plaintext, not hashed) between the config value and the user-supplied password.\r\n\r\nA successful match grants role=2 (admin-level access) and creates a valid session. The rzadmin username is never checked — any username works with the backdoor"
    },
    {
      "lang": "es",
      "value": "El binario del servidor web /bin/httpd contiene un mecanismo de autenticación de puerta trasera oculto en la función login() en 004c88b8.\n\n- La función contiene una ruta de autenticación normal utilizando verificación de contraseña basada en MD5/hash (prod_encode64/PasswordToMd5/check_rand_key).\n- Después de que la autenticación normal falla, llama a GetValue(’sys.rzadmin.password’) para leer una contraseña de puerta trasera de la configuración del dispositivo.\n- Realiza una comparación strcmp() directa (texto plano, no hasheado) entre el valor de configuración y la contraseña proporcionada por el usuario.\n\nUna coincidencia exitosa otorga rol=2 (acceso a nivel de administrador) y crea una sesión válida. El nombre de usuario rzadmin nunca se verifica - cualquier nombre de usuario funciona con la puerta trasera"
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Tenda",
          "product": "firmware",
          "versions": [
            {
              "version": "US_AC6V2.0RTL_V15.03.06.51_multi_T",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Tenda",
          "product": "firmware",
          "versions": [
            {
              "version": "US_AC5V1.0RTL_V15.03.06.48_multi_TDE01",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Tenda",
          "product": "firmware",
          "versions": [
            {
              "version": "US_AC10V1.0re_V15.03.06.46_multi_TDE01",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Tenda",
          "product": "firmware",
          "versions": [
            {
              "version": "US_W15EV1.0br_V15.11.0.5(1068_1567_841)_EN_TDE",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Tenda",
          "product": "firmware",
          "versions": [
            {
              "version": "US_FH1201V1.0BR_V1.2.0.14(408)_EN_TD",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "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:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-08T03:56:43.961536Z",
          "id": "CVE-2026-11405",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://cwe.mitre.org/data/definitions/912.html",
      "source": "[email protected]"
    },
    {
      "url": "https://kb.cert.org/vuls/id/213560",
      "source": "[email protected]"
    },
    {
      "url": "https://www.kb.cert.org/vuls/id/213560",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ]
}