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CVE-2021-31800

Estado: ModificadaCrítica (9.8)—💥 PoC

Multiple path traversal vulnerabilities exist in smbserver.py in Impacket through 0.9.22. An attacker that connects to a running smbserver instance can list and write to arbitrary files via ../ directory traversal. This could potentially be abused to achieve arbitrary code execution by replacing /etc/shadow or an SSH authorized key.

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 (2)

Fedoraproject — FedoraSecureauth — Impacket

CWE

Referencias

JSON original (NVD)

Mostrar
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  "id": "CVE-2021-31800",
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      "value": "Multiple path traversal vulnerabilities exist in smbserver.py in Impacket through 0.9.22. An attacker that connects to a running smbserver instance can list and write to arbitrary files via ../ directory traversal. This could potentially be abused to achieve arbitrary code execution by replacing /etc/shadow or an SSH authorized key."
    },
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      "lang": "es",
      "value": "Se presentan múltiples vulnerabilidades de salto de ruta en el archivo smbserver.py en Impacket versiones hasta 0.9.22. Un atacante que se conecta a una instancia de smbserver en ejecución puede enumerar y escribir en archivos arbitrarios por medio de un salto de directorio ../. Esto podría potencialmente ser abusado para lograr una ejecución de código arbitraria al reemplazar /etc/shadow o una clave SSH autorizada"
    }
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  "lastModified": "2026-06-17T03:52:15.463",
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