CVE-2022-49556

Estado: AnalizadaAlta (7.1)—

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

KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak

For some sev ioctl interfaces, the length parameter that is passed maybe less than or equal to SEV_FW_BLOB_MAX_SIZE, but larger than the data that PSP firmware returns. In this case, kmalloc will allocate memory that is the size of the input rather than the size of the data. Since PSP firmware doesn't fully overwrite the allocated buffer, these sev ioctl interface may return uninitialized kernel slab memory.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Puntuación base: 7.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.27%
Percentil entre todas las CVEs puntuadas: 18
Fecha de la puntuación: 5/10/2026

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 principalT1552.007 Container APIcredential access75 %

Acceso local sin interacción (AV:L, PR:L, UI:N) explota falla en asignación de memoria para leer datos del kernel no inicializados.

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

User Account Management Threat Intelligence Program Privileged Account Management Network Segmentation Limit Access to Resource Over Network Execution Prevention

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

Mostrar

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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak\n\nFor some sev ioctl interfaces, the length parameter that is passed maybe\nless than or equal to SEV_FW_BLOB_MAX_SIZE, but larger than the data\nthat PSP firmware returns. In this case, kmalloc will allocate memory\nthat is the size of the input rather than the size of the data.\nSince PSP firmware doesn't fully overwrite the allocated buffer, these\nsev ioctl interface may return uninitialized kernel slab memory."
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      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: KVM: SVM: Usar kzalloc para interfaces sev ioctl para evitar fugas de datos del kernel Para algunas interfaces sev ioctl, el parámetro de longitud que se pasa puede ser menor o igual a SEV_FW_BLOB_MAX_SIZE, pero mayor que los datos que devuelve el firmware de PSP. En este caso, kmalloc asignará memoria que sea del tamaño de la entrada en lugar del tamaño de los datos. Dado que el firmware de PSP no sobrescribe por completo el búfer asignado, estas interfaces sev ioctl pueden devolver memoria de losa de kernel no inicializada."
    }
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