CVE-2025-21671
In the Linux kernel, the following vulnerability has been resolved:
zram: fix potential UAF of zram table
If zram_meta_alloc failed early, it frees allocated zram->table without setting it NULL. Which will potentially cause zram_meta_free to access the table if user reset an failed and uninitialized device.
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: 0.22%
- Percentil entre todas las CVEs puntuadas: 11
- 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.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation75 % - Impacto principal
T1059Command and Scripting Interpreterexecution60 %
Acceso local (AV:L) sin interacción de usuario permite escalar privilegios mediante UAF en tabla zram; permite ejecución de código con privilegios elevados en 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
Tecnologías afectadas (1)
CWE
- CWE-416
- CWE-416
Referencias
- https://git.kernel.org/stable/c/212fe1c0df4a150fb6298db2cfff267ceaba5402
- https://git.kernel.org/stable/c/571d3f6045cd3a6d9f6aec33b678f3ffe97582ef
- https://git.kernel.org/stable/c/902ef8f16d5ca77edc77c30656be54186c1e99b7
- https://git.kernel.org/stable/c/fe3de867f94819ba0f28e035c0b0182150147d95
- https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
JSON original (NVD)
Mostrar
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