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CVE-2021-3492

Estado: ModificadaAlta (7.8)—💥 PoC

Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.

CVSS

Probabilidad de explotación (EPSS)

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).

💥 Exploits públicos

Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.

⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.

Tecnologías afectadas (1)

Canonical — Ubuntu Linux

CWE

Referencias

JSON original (NVD)

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      "value": "Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562."
    },
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      "lang": "es",
      "value": "Shiftfs, un sistema de archivos de apilamiento fuera del árbol incluido en los kernels de Ubuntu Linux, no manejaba apropiadamente los fallos que ocurrían durante la función copy_from_user(). Esto podría conllevar a una situación de doble liberación o a que la memoria no sea liberada del todo. Un atacante podría usar esto para causar una denegación de servicio (agotamiento de la memoria del kernel) u alcanzar privilegios por medio de la ejecución de código arbitrario. También se conoce como ZDI-CAN-13562"
    }
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