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CVE-2020-14367

Estado: ModificadaMedia (6)—

A flaw was found in chrony versions before 3.5.1 when creating the PID file under the /var/run/chrony folder. The file is created during chronyd startup while still running as the root user, and when it's opened for writing, chronyd does not check for an existing symbolic link with the same file name. This flaw allows an attacker with privileged access to create a symlink with the default PID file name pointing to any destination file in the system, resulting in data loss and a denial of service due to the path traversal.

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 (3)

Canonical — Ubuntu LinuxFedoraproject — FedoraTuxfamily — Chrony

CWE

Referencias

JSON original (NVD)

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      "value": "A flaw was found in chrony versions before 3.5.1 when creating the PID file under the /var/run/chrony folder. The file is created during chronyd startup while still running as the root user, and when it's opened for writing, chronyd does not check for an existing symbolic link with the same file name. This flaw allows an attacker with privileged access to create a symlink with the default PID file name pointing to any destination file in the system, resulting in data loss and a denial of service due to the path traversal."
    },
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      "lang": "es",
      "value": "Se detectó un fallo en chrony versiones anteriores a 3.5.1, al crear el archivo PID en la carpeta /var/run/chrony. El archivo es creado durante el inicio de chronyd mientras aún se ejecuta como usuario root, y cuando se abre para escritura, chronyd no busca un enlace simbólico existente con el mismo nombre de archivo. Este fallo permite a un atacante con acceso privilegiado crear un enlace simbólico con el nombre de archivo PID predeterminado apuntando a cualquier archivo de destino en el sistema, resultando en la pérdida de datos y una denegación de servicio debido a un salto de ruta."
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  "lastModified": "2026-06-17T02:54:38.127",
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