CVE-2026-43391

Estado: ModificadaAlta (8.8)—

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

nsfs: tighten permission checks for handle opening

Even privileged services should not necessarily be able to see other privileged service's namespaces so they can't leak information to each other. Use may_see_all_namespaces() helper that centralizes this policy until the nstree adapts.

CVSS

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

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.17%
Percentil entre todas las CVEs puntuadas: 6
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 escalation90 %
Impacto principalT1005 Data from Local Systemcollection75 %
Impacto secundarioT1552 Unsecured Credentialscredential access70 %

Vulnerabilidad de escalada de privilegios en kernel Linux (AV:L, PR:L) que permite a servicios privilegiados acceder a namespaces ajenos, filtrando información sensible de otros servicios.

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

Update Software Active Directory Configuration User Training Threat Intelligence Program Restrict File and Directory Permissions Privileged Account Management

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

Mostrar

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