CVE-2026-15806

{
  "id": "CVE-2026-15806",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-18T16:17:02.220",
  "lastModified": "2026-10-22T22:10:00.250",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The HTTPPasswordMgr class in the urllib.request module, along with its subclasses HTTPPasswordMgrWithDefaultRealm and HTTPPasswordMgrWithPriorAuth, did not take the URL scheme into account when matching stored credentials against a requested URL. Credentials added for an https:// URL were also used for requests to the same host over http://, so an attacker able to redirect or downgrade a client to plain HTTP (for example, via an HTTPS-to-HTTP redirect or an on-path position) could capture credentials in cleartext. Credentials added for http:// URLs could likewise be sent over https://.\n\nCredential matching is now scoped by URL scheme. Credentials registered with a URL that includes a scheme are only used for requests with the same scheme. Credentials registered with a bare authority (such as example.com or example.com:8080) continue to match any scheme, preserving compatibility with existing code, including proxy authentication.\n\nUsers who cannot upgrade immediately can mitigate by ensuring that applications never make plain http:// requests to hosts for which credentials are registered, for example by not following redirects to http:// URLs."
    },
    {
      "lang": "es",
      "value": "La clase HTTPPasswordMgr en el módulo urllib.request, junto con sus subclases HTTPPasswordMgrWithDefaultRealm y HTTPPasswordMgrWithPriorAuth, no tenían en cuenta el esquema de la URL al hacer coincidir las credenciales almacenadas con una URL solicitada. Las credenciales añadidas para una URL https:// también se utilizaban para solicitudes al mismo host a través de http://, por lo que un atacante capaz de redirigir o degradar a un cliente a HTTP simple (por ejemplo, mediante una redirección de HTTPS a HTTP o una posición en la ruta) podría capturar credenciales en texto claro. Las credenciales añadidas para URLs http:// de igual manera podrían enviarse a través de https://.\n\nLa coincidencia de credenciales ahora está limitada por el esquema de la URL. Las credenciales registradas con una URL que incluye un esquema solo se utilizan para solicitudes con el mismo esquema. Las credenciales registradas con una autoridad simple (como example.com o example.com:8080) continúan coincidiendo con cualquier esquema, preservando la compatibilidad con el código existente, incluida la autenticación de proxy.\n\nLos usuarios que no pueden actualizar de inmediato pueden mitigar asegurándose de que las aplicaciones nunca realicen solicitudes http:// simples a hosts para los que las credenciales están registradas, por ejemplo, al no seguir redirecciones a URLs http://."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Python Software Foundation",
          "product": "CPython",
          "defaultStatus": "unaffected",
          "repo": "https://github.com/python/cpython",
          "versions": [
            {
              "version": "0",
              "lessThan": "3.10.22",
              "versionType": "python",
              "status": "affected"
            },
            {
              "version": "3.11.0",
              "lessThan": "3.11.17",
              "versionType": "python",
              "status": "affected"
            },
            {
              "version": "3.12.0",
              "lessThan": "3.12.15",
              "versionType": "python",
              "status": "affected"
            },
            {
              "version": "3.13.0",
              "lessThan": "3.13.16",
              "versionType": "python",
              "status": "affected"
            },
            {
              "version": "3.14.0",
              "lessThan": "3.14.8",
              "versionType": "python",
              "status": "affected"
            },
            {
              "version": "3.15.0a1",
              "lessThan": "3.15.0rc2",
              "versionType": "python",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 6.0,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "attackRequirements": "PRESENT",
          "privilegesRequired": "NONE",
          "userInteraction": "PASSIVE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-18T18:56:36.349726Z",
          "id": "CVE-2026-15806",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-319"
        },
        {
          "lang": "en",
          "value": "CWE-522"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/python/cpython/commit/641be42bb07921ba0f8bffe228b1dc706b092ef6",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/commit/851cf9a7142ecbdd39f831055533f58284ad2bcc",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/commit/95355ee3a8e1d3c3d4858d1973aa42a9b91a2801",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/commit/a0d023fbd23773e24b35d8368789470e22cda5d8",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/commit/a2773a34183b7d94a243bb98fd658926cc5348ce",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/commit/a7bb524fef61f77ede01f660ffbd591e1d5837ce",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/commit/dac88d8615078c55f1304ea4c7a2d822700d4e5a",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/issues/155694",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/python/cpython/pull/155696",
      "source": "[email protected]"
    },
    {
      "url": "https://mail.python.org/archives/list/[email protected]/thread/3OKPE5S75KDNA7FY7AI3PL2MXM2X5RB3/",
      "source": "[email protected]"
    },
    {
      "url": "http://www.openwall.com/lists/oss-security/2026/08/18/3",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://github.com/python/cpython/issues/155694",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}