CVE-2026-49420

Estado: AnalizadaAlta (8.8)—

The RTSP handler in libalias rewrote outgoing packets into a fixed-length stack buffer without checking whether the rewritten data fit in the buffer, or whether the result fit back in the original packet.

A host sending crafted RTSP traffic from inside a NAT gateway using libalias can overflow a stack buffer, potentially achieving remote code execution in the kernel (when using ipfw(4) NAT) or in the natd(8) process (which generally runs as the root user).

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:A/AC:L/PR:N/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: 0.42%
Percentil entre todas las CVEs puntuadas: 34
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.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement85 %
Impacto principalT1059 Command and Scripting Interpreterexecution80 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation75 %

Vector AV:A (red adyacente, sin privilegios) → T1210. Stack buffer overflow permite ejecución de código (T1059) en kernel/natd con privilegios root (T1068). Texto explícito: RCE potencial.

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

https://security.freebsd.org/advisories/FreeBSD-SA-26:41.libalias.asc

JSON original (NVD)

Mostrar

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