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CVE-2021-44731

Status: ModifiedHigh (7.8)—

A race condition existed in the snapd 2.54.2 snap-confine binary when preparing a private mount namespace for a snap. This could allow a local attacker to gain root privileges by bind-mounting their own contents inside the snap's private mount namespace and causing snap-confine to execute arbitrary code and hence gain privilege escalation. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1

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 (4)

Canonical — SnapdCanonical — Ubuntu LinuxDebian — Debian LinuxFedoraproject — Fedora

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2021-44731",
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      "description": [
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      "lang": "en",
      "value": "A race condition existed in the snapd 2.54.2 snap-confine binary when preparing a private mount namespace for a snap. This could allow a local attacker to gain root privileges by bind-mounting their own contents inside the snap's private mount namespace and causing snap-confine to execute arbitrary code and hence gain privilege escalation. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1"
    },
    {
      "lang": "es",
      "value": "Se presentaba una condición de carrera en snapd versión 2.54.2 en el binario snap-confine cuando era preparado un espacio de nombres de montaje privado para un snap. Esto podía permitir a un atacante local alcanzar privilegios de root al montar su propio contenido dentro del espacio de nombres de montaje privado del snap y causar que snap-confine ejecutara código arbitrario y por lo tanto obtuviera una escalada de privilegios. Corregido en snapd versiones 2.54.3+18.04, 2.54.3+20.04 y 2.54.3+21.10.1"
    }
  ],
  "lastModified": "2026-06-17T04:12:46.470",
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