CVE-2026-39421
MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a sandbox escape vulnerability in the ToolExecutor component. By leveraging Python's ctypes library to execute raw system calls, an authenticated attacker with workspace privileges can bypass the LD_PRELOAD-based sandbox.so module to achieve arbitrary code execution via direct kernel system calls, enabling full network exfiltration and container compromise. The library intercepts critical standard system functions such as execve, system, connect, and open. It also intercepts mprotect to prevent PROT_EXEC (executable memory) allocations within the sandboxed Python processes, but pkey_mprotect is not blocked. This issue has been fixed in version 2.8.0.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L
- Puntuación base: 7.4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.45%
- Percentil entre todas las CVEs puntuadas: 37
- 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.
- Explotación
T1210Exploitation of Remote Serviceslateral movement85 % - Impacto principal
T1059Command and Scripting Interpreterexecution90 % - Impacto secundario
T1005Data from Local Systemcollection75 % - Impacto secundario
T1041Exfiltration Over C2 Channelexfiltration80 %
Autenticado con privilegios (PR:L) explotando escape de sandbox en componente remoto para ejecutar código arbitrario y exfiltrar datos de red; CVSS remota y multiservicio (S:C) confirma T1210 con impactos de ejecución de comandos, acceso a datos y exfiltración.
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-94, CWE-693
Referencias
JSON original (NVD)
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