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CVE-2025-62494

Estado: AnalizadaAlta (7.1)—

A type confusion vulnerability exists in the handling of the string addition (+) operation within the QuickJS engine.

This mismatch between the assumed type (string) and the actual type allows an attacker to control the data structure being processed by the concatenation logic, resulting in a type confusion condition. This can lead to out-of-bounds memory access, potentially resulting in memory corruption and arbitrary code execution in the context of the QuickJS runtime.

Detalles técnicos trazas, registros y código del informe original
  *  The code first checks if the left-hand operand is a string.

  *  It then attempts to convert the right-hand operand to a primitive value using JS_ToPrimitiveFree. This conversion can trigger a callback (e.g., toString or valueOf).

  *  During this callback, an attacker can modify the type of the left-hand operand in memory, changing it from a string to a different type (e.g., an object or an array).

  *  The code then proceeds to call JS_ConcatStringInPlace, which still treats the modified left-hand value as a string.

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.

Type confusion en QuickJS requiere interacción del usuario (UI:P) para ejecutar script JavaScript. Permite ejecución de código arbitrario (corrupción de memoria) e inyección de datos en tiempo de ejecución.

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 ContentRestrict File and Directory PermissionsPrivileged Account ManagementRemote Data StorageLimit Software InstallationExecution Prevention

Tecnologías afectadas (1)

Quickjs Project — Quickjs

CWE

Referencias

JSON original (NVD)

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