CVE-2022-49935

Estado: ModificadaAlta (7.8)—

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

dma-buf/dma-resv: check if the new fence is really later

Previously when we added a fence to a dma_resv object we always assumed the the newer than all the existing fences.

With Jason's work to add an UAPI to explicit export/import that's not necessary the case any more. So without this check we would allow userspace to force the kernel into an use after free error.

Since the change is very small and defensive it's probably a good idea to backport this to stable kernels as well just in case others are using the dma_resv object in the same way.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.8

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 escalation85 %
Impacto principalT1059 Command and Scripting Interpreterexecution70 %

CVE local (AV:L/PR:L) sin interacción permite escalada de privilegios por use-after-free. La ejecución de código es consecuencia de corromper memoria kernel.

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

Execution Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Behavior Prevention on Endpoint

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-416

Referencias

JSON original (NVD)

Mostrar

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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndma-buf/dma-resv: check if the new fence is really later\n\nPreviously when we added a fence to a dma_resv object we always\nassumed the the newer than all the existing fences.\n\nWith Jason's work to add an UAPI to explicit export/import that's not\nnecessary the case any more. So without this check we would allow\nuserspace to force the kernel into an use after free error.\n\nSince the change is very small and defensive it's probably a good\nidea to backport this to stable kernels as well just in case others\nare using the dma_resv object in the same way."
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