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CVE-2026-66321

Estado: AnalizadaCrítica (9.6)—

Access of resource using incompatible type ('type confusion') in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

AV:N, UI:R e intentar ejecutar código en navegador Chromium. Type confusion (CWE-843) requiere interacción del usuario para abrir contenido malicioso, activando T1203 (ejecución en cliente). El resultado es ejecución de código arbitrario (T1059).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Restrict Web-Based ContentPrivileged Account ManagementLimit Software InstallationExecution PreventionBehavior Prevention on EndpointDisable or Remove Feature or Program

Tecnologías afectadas (1)

Microsoft — Edge Chromium

CWE

Referencias

JSON original (NVD)

Mostrar
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          "options": [
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            },
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        "source": "nvd@nist.gov",
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      "tags": [
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  ],
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      "source": "secure@microsoft.com",
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      "value": "Access of resource using incompatible type ('type confusion') in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network."
    }
  ],
  "lastModified": "2026-08-06T17:06:42.727",
  "configurations": [
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