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CVE-2021-3996

Estado: ModificadaMedia (5.5)—

A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem. This flaw allows a local user on a vulnerable system to unmount other users' filesystems that are either world-writable themselves (like /tmp) or mounted in a world-writable directory. An attacker may use this flaw to cause a denial of service to applications that use the affected filesystems.

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).

Tecnologías afectadas (2)

Fedoraproject — FedoraKernel — Util-linux

CWE

Referencias

JSON original (NVD)

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    {
      "lang": "en",
      "value": "A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem. This flaw allows a local user on a vulnerable system to unmount other users' filesystems that are either world-writable themselves (like /tmp) or mounted in a world-writable directory. An attacker may use this flaw to cause a denial of service to applications that use the affected filesystems."
    },
    {
      "lang": "es",
      "value": "Se ha encontrado un error lógico en la biblioteca libmount de util-linux en la función que permite a un usuario no privilegiado desmontar un sistema de archivos FUSE. Este fallo permite a un usuario local en un sistema vulnerable desmontar los sistemas de archivos de otros usuarios que son de escritura mundial (como /tmp) o que están montados en un directorio de escritura mundial. Un atacante puede usar este fallo para causar una denegación de servicio a las aplicaciones que usan los sistemas de archivos afectados."
    }
  ],
  "lastModified": "2026-06-17T04:06:21.753",
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