CVE-2026-64284
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Ensure vendor's exit handler runs before fastpath userspace exits
Move the handling of fastpath userspace exits into vendor code to ensure KVM runs vendor specific operations that need to run before userspace gains control of the vCPU. E.g. for VMX (and soon to be for SVM as well), KVM needs to flush the PML buffer prior to exiting to userspace, otherwise any memory written by the final KVM_RUN might never be flagged as dirty.
Note, waiting to snapshot CR0 and CR3 until svm_handle_exit() is flawed in general, as that risks consuming stale state in a fastpath handler. That will be addressed in a future change.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
- Puntuación base: 7.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.13%
- Percentil entre todas las CVEs puntuadas: 2
- 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.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation75 % - Impacto principal
T1565.001Stored Data Manipulationimpact65 % - Impacto secundario
T1499.004Application or System Exploitationimpact55 %
Vulnerabilidad de escalada local (AV:L, PR:L) en kernel Linux que compromete integridad de datos en memoria (CWE-367: TOCTOU) y disponibilidad por corrupción de estado de vCPU.
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
Tecnologías afectadas (1)
CWE
- CWE-367
Referencias
JSON original (NVD)
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