CVE-2026-31449

Estado: ModificadaAlta (7.8)—

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

ext4: validate p_idx bounds in ext4_ext_correct_indexes

ext4_ext_correct_indexes() walks up the extent tree correcting index entries when the first extent in a leaf is modified. Before accessing path[k].p_idx->ei_block, there is no validation that p_idx falls within the valid range of index entries for that level.

If the on-disk extent header contains a corrupted or crafted eh_entries value, p_idx can point past the end of the allocated buffer, causing a slab-out-of-bounds read.

Fix this by validating path[k].p_idx against EXT_LAST_INDEX() at both access sites: before the while loop and inside it.

Leer descripción completaMostrar menos

Return -EFSCORRUPTED if the index pointer is out of range, consistent with how other bounds violations are handled in the ext4 extent tree code.

CVSS

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

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.20%
Percentil entre todas las CVEs puntuadas: 8
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.

ExplotaciónT1203 Exploitation for Client Executionexecution85 %
Impacto principalT1005 Data from Local Systemcollection75 %

AV:L, UI:R indica ejecución en cliente (fichero corrupto). Lectura fuera de límites (CWE-125) de estructura en memoria del kernel; potencial para divulgar datos o causar DoS.

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

Application Isolation and Sandboxing Exploit Protection Update Software Data Loss Prevention

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-125

Referencias

JSON original (NVD)

Mostrar

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