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CVE-2026-76957

Estado: AnalizadaAlta (7.8)—

libexpat before 2.8.4 lacks handler call depth tracking with custom encoding callbacks. Thus, a use-after-free can occur. NOTE: this is similar to CVE-2026-50219, CVE-2026-56131 and CVE-2026-56412.

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.

Vulnerabilidad de uso después de liberación (CWE-416) en libexpat con acceso local (AV:L) sin interacción (UI:N) permite escalada de privilegios a ejecución de código arbitrario.

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

Execution PreventionThreat Intelligence ProgramRestrict Web-Based ContentPrivileged Account ManagementLimit Software InstallationBehavior Prevention on Endpoint

Tecnologías afectadas (1)

Libexpat Project — Libexpat

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2026-76957",
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          "timestamp": "2026-08-20T15:05:41.792254Z"
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  "lastModified": "2026-09-08T20:56:31.860",
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