CVE-2026-31773

Estado: AnalizadaAlta (8.8)—

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

Bluetooth: SMP: derive legacy responder STK authentication from MITM state

The legacy responder path in smp_random() currently labels the stored STK as authenticated whenever pending_sec_level is BT_SECURITY_HIGH. That reflects what the local service requested, not what the pairing flow actually achieved.

For Just Works/Confirm legacy pairing, SMP_FLAG_MITM_AUTH stays clear and the resulting STK should remain unauthenticated even if the local side requested HIGH security. Use the established MITM state when storing the responder STK so the key metadata matches the pairing result.

Leer descripción completaMostrar menos

This also keeps the legacy path aligned with the Secure Connections code, which already treats JUST_WORKS/JUST_CFM as unauthenticated.

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: 0.46%
Percentil entre todas las CVEs puntuadas: 37
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 movement65 %
Impacto principalT1078.004 Cloud Accountsstealth · persistence · privilege escalation · initial access60 %
Impacto secundarioT1556 Modify Authentication Processdefense impairment · persistence · credential access55 %

Bluetooth SMP en kernel Linux, acceso red adyacente (AV:A). Impacto: escalada de privilegios de autenticación (STK débil sin MITM) y potencial secuestro de identidad Bluetooth.

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

Privileged Account Management User Account Management Password Policies Multi-factor Authentication Active Directory Configuration Vulnerability Scanning

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

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