CVE-2026-46234
In the Linux kernel, the following vulnerability has been resolved:
vsock: fix buffer size clamping order
In vsock_update_buffer_size(), the buffer size was being clamped to the maximum first, and then to the minimum. If a user sets a minimum buffer size larger than the maximum, the minimum check overrides the maximum check, inverting the constraint.
This breaks the intended socket memory boundaries by allowing the vsk->buffer_size to grow beyond the configured vsk->buffer_max_size.
Fix this by checking the minimum first, and then the maximum. This ensures the buffer size never exceeds the buffer_max_size.
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: 0.18%
- Percentil entre todas las CVEs puntuadas: 6
- 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 escalation85 % - Impacto principal
T1059Command and Scripting Interpreterexecution70 % - Impacto secundario
T1499.004Application or System Exploitationimpact65 %
AV:L PR:L sin UI permite escalada local. La inversión de restricciones de buffer en vsock permite que un proceso local no privilegiado cause escritura fuera de límites (CWE-787), ejecutando código o causando 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
Tecnologías afectadas (1)
CWE
- CWE-787
Referencias
- https://git.kernel.org/stable/c/01ef69785dc3162f588a361ab770b1e312800188
- https://git.kernel.org/stable/c/0b68881501460c3761f196469e1e503218c5e536
- https://git.kernel.org/stable/c/2602f7bb5818e92315feeaeb71d8ce4d5c9ab160
- https://git.kernel.org/stable/c/310da27932dd0afe7ce7456dfe1f0814c3301f41
- https://git.kernel.org/stable/c/a998a7e250bf976539e05a00ec64a81292afecaa
- https://git.kernel.org/stable/c/caf11dfea5233a69298a1c448bbf8d1639c80536
- https://git.kernel.org/stable/c/d114bfdc9b76bf93b881e195b7ec957c14227bab
- https://git.kernel.org/stable/c/f6ec135941d2c1c2dbb87b5ce1783f4f6ac6ccca
JSON original (NVD)
Mostrar
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