CVE-2026-4747

Estado: AnalizadaAlta (8.8)—

Each RPCSEC_GSS data packet is validated by a routine which checks a signature in the packet. This routine copies a portion of the packet into a stack buffer, but fails to ensure that the buffer is sufficiently large, and a malicious client can trigger a stack overflow. Notably, this does not require the client to authenticate itself first.

As kgssapi.ko's RPCSEC_GSS implementation is vulnerable, remote code execution in the kernel is possible by an authenticated user that is able to send packets to the kernel's NFS server while kgssapi.ko is loaded into the kernel.

In userspace, applications which have librpcgss_sec loaded and run an RPC server are vulnerable to remote code execution from any client able to send it packets. We are not aware of any such applications in the FreeBSD base system.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 8.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 1.11%
Percentil entre todas las CVEs puntuadas: 65
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.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement95 %
Impacto principalT1059 Command and Scripting Interpreterexecution90 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation75 %

Vector CVSS requiere PR:L (privilegios locales) en red → T1210. Desbordamiento de pila en RPCSEC_GSS permite ejecución de código en kernel (T1059) y acceso root (T1068).

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

Threat Intelligence Program Privileged Account Management Execution Prevention Disable or Remove Feature or Program Application Isolation and Sandboxing Exploit Protection

Tecnologías afectadas (1)

Freebsd — Freebsd

CWE

CWE-121

Referencias

JSON original (NVD)

Mostrar

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      "value": "Each RPCSEC_GSS data packet is validated by a routine which checks a signature in the packet.  This routine copies a portion of the packet into a stack buffer, but fails to ensure that the buffer is sufficiently large, and a malicious client can trigger a stack overflow.  Notably, this does not require the client to authenticate itself first.\n\nAs kgssapi.ko's RPCSEC_GSS implementation is vulnerable, remote code execution in the kernel is possible by an authenticated user that is able to send packets to the kernel's NFS server while kgssapi.ko is loaded into the kernel.\n\nIn userspace, applications which have librpcgss_sec loaded and run an RPC server are vulnerable to remote code execution from any client able to send it packets.  We are not aware of any such applications in the FreeBSD base system."
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      "value": "Cada paquete de datos RPCSEC_GSS es validado por una rutina que verifica una firma en el paquete. Esta rutina copia una porción del paquete en un búfer de pila, pero no asegura que el búfer sea lo suficientemente grande, y un cliente malicioso puede desencadenar un desbordamiento de pila. En particular, esto no requiere que el cliente se autentique primero.\n\nDado que la implementación RPCSEC_GSS de kgssapi.ko es vulnerable, la ejecución remota de código en el kernel es posible por un usuario autenticado que sea capaz de enviar paquetes al servidor NFS del kernel mientras kgssapi.ko está cargado en el kernel.\n\nEn el espacio de usuario, las aplicaciones que tienen librpcgss_sec cargado y ejecutan un servidor RPC son vulnerables a la ejecución remota de código desde cualquier cliente capaz de enviarle paquetes. No tenemos conocimiento de ninguna aplicación de este tipo en el sistema base de FreeBSD."
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  "lastModified": "2026-06-17T10:57:09.993",
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