CVE-2020-7247

Estado: AnalizadaCrítica (9.8)⚠ Explotación activa

smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" default configuration. The issue exists because of an incorrect return value upon failure of input validation.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 99%
Percentil entre todas las CVEs puntuadas: 100
Fecha de la puntuación: 29/9/2026

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).

CISA KEV — explotada activamente

Añadida al catálogo: 25/3/2022
Plazo de remediación: 15/4/2022
Uso conocido en ransomware: Unknown

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access95 %
Impacto principalT1059 Command and Scripting Interpreterexecution90 %
Impacto secundarioT1498.002 Reflection Amplificationimpact40 %

CWE-78 command injection en servicio SMTP expuesto (AV:N/AC:L/PR:N) permite ejecución de comandos como root. Metacaracteres en MAIL FROM demuestran RCE; ransomware indica potencial DoS.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Privileged Account Management Filter Network Traffic Vulnerability Scanning Restrict Web-Based Content Network Segmentation Limit Software Installation

Tecnologías afectadas (4)

Canonical — Ubuntu Linux Debian — Debian Linux Fedoraproject — Fedora Openbsd — Opensmtpd

CWE

CWE-78, CWE-755
CWE-755

Referencias

JSON original (NVD)

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