CVE-2025-21734

Estado: ModificadaAlta (7.8)—

In the Linux kernel, the following vulnerability has been resolved:

misc: fastrpc: Fix copy buffer page size

For non-registered buffer, fastrpc driver copies the buffer and pass it to the remote subsystem. There is a problem with current implementation of page size calculation which is not considering the offset in the calculation. This might lead to passing of improper and out-of-bounds page size which could result in memory issue. Calculate page start and page end using the offset adjusted address instead of absolute address.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.21%
Percentil entre todas las CVEs puntuadas: 10
Fecha de la puntuación: 6/10/2026

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.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Impacto principalT1059 Command and Scripting Interpreterexecution70 %

Vulnerabilidad de buffer overflow (CWE-787) en kernel local con PR:L (requiere acceso local con privilegios) que permite escalada hacia ejecución arbitraria de código en contexto privilegiado.

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 Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Behavior Prevention on Endpoint

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-787

Referencias

JSON original (NVD)

Mostrar

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      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: misc: fastrpc: Se corrige el tamaño de página del búfer de copia Para un búfer no registrado, el controlador fastrpc copia el búfer y lo pasa al subsistema remoto. Hay un problema con la implementación actual del cálculo del tamaño de página que no considera el desplazamiento en el cálculo. Esto podría provocar que se pase un tamaño de página incorrecto y fuera de los límites, lo que podría generar un problema de memoria. Calcule el inicio y el final de la página utilizando la dirección ajustada por desplazamiento en lugar de la dirección absoluta."
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