CVE-2021-20090

Estado: AnalizadaCrítica (9.8)⚠ Explotación activa💥 Exploit

A path traversal vulnerability in the web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 could allow unauthenticated remote attackers to bypass authentication.

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: 100%
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: 3/11/2021
Plazo de remediación: 17/11/2021
Uso conocido en ransomware: Unknown

💥 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.

Plantilla de Nuclei (detección automática y masiva) · Buffalo WSR-2533DHPL2 - Path Traversal

🎯 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 principalT1005 Data from Local Systemcollection85 %
Impacto secundarioT1078 Valid Accountsstealth · persistence · privilege escalation · initial access80 %

Path traversal (CWE-22) en interfaz web sin autenticación (PR:N, UI:N) permite eludir controles de acceso remoto. AV:N confirma T1190. Impacto: lectura de datos sensibles (C:H) y evasión de autenticación (I:H implica manipulación de sesiones/T1078).

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 Application Developer Guidance Active Directory Configuration Vulnerability Scanning User Training User Account Management

Tecnologías afectadas (2)

Buffalo — Wsr-2533dhp3-bk Firmware Buffalo — Wsr-2533dhpl2-bk Firmware

CWE

CWE-22
CWE-22

Referencias

JSON original (NVD)

Mostrar

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