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CVE-2026-31735

Estado: AnalizadaAlta (8.8)—

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

iommupt: Fix short gather if the unmap goes into a large mapping

unmap has the odd behavior that it can unmap more than requested if the ending point lands within the middle of a large or contiguous IOPTE.

In this case the gather should flush everything unmapped which can be larger than what was requested to be unmapped. The gather was only flushing the range requested to be unmapped, not extending to the extra range, resulting in a short invalidation if the caller hits this special condition.

This was found by the new invalidation/gather test I am adding in preparation for ARMv8. Claude deduced the root cause.

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As far as I remember nothing relies on unmapping a large entry, so this is likely not a triggerable bug.

CVSS

Probabilidad de explotación (EPSS)

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.

Acceso local sin interacción (AV:L, UI:N, PR:L) sugiere T1068. La falta de invalidación de TLB podría permitir acceso a memoria no autorizada o DoS; bug teórico sin demostración de explotabilidad.

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 ProgramFilter Network TrafficExecution PreventionEncrypt Sensitive InformationApplication Isolation and SandboxingExploit Protection

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

Referencias

JSON original (NVD)

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