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CVE-2021-20317

Status: ModifiedMedium (4.4)—

A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (2)

Debian — Debian LinuxLinux — Linux Kernel

CWEs

References

Raw JSON (NVD)

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    },
    {
      "lang": "es",
      "value": "Se ha encontrado un fallo en el kernel de Linux. Un árbol de temporizadores corrompido hacía que faltara el despertar de la tarea en la función timerqueue_add en el archivo lib/timerqueue.c. Este defecto permite a un atacante local con privilegios de usuario especiales causar una denegación de servicio, ralentizando y eventualmente deteniendo el sistema mientras se ejecuta OSP"
    }
  ],
  "lastModified": "2026-06-17T03:33:39.730",
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