CVE-2026-31720

Estado: AnalizadaAlta (7.8)—

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

usb: gadget: f_uac1_legacy: validate control request size

f_audio_complete() copies req->length bytes into a 4-byte stack variable:

req->length is derived from the host-controlled USB request path, which can lead to a stack out-of-bounds write.

Validate req->actual against the expected payload size for the supported control selectors and decode only the expected amount of data.

This avoids copying a host-influenced length into a fixed-size stack object.

Detalles técnicos trazas, registros y código del informe original

  u32 data = 0;
  memcpy(&data, req->buf, req->length);

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: 0.18%
Percentil entre todas las CVEs puntuadas: 6
Fecha de la puntuación: 5/10/2026

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 Interpreterexecution75 %
Impacto secundarioT1499.004 Application or System Exploitationimpact60 %

Acceso local (AV:L, PR:L) sin interacción del usuario permite escribir fuera de límites en la pila del kernel para ejecutar código arbitrario o causar denegación de servicio.

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 Filter Network Traffic

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-787

Referencias

JSON original (NVD)

Mostrar

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