CVE-2021-47940

Estado: AplazadaCrítica (9.3)—

WordPress Plugin Download From Files version 1.48 and earlier contains an arbitrary file upload vulnerability that allows unauthenticated attackers to upload malicious files by exploiting the AJAX fileupload action. Attackers can send POST requests to the admin-ajax.php endpoint with the download_from_files_617_fileupload action, manipulating the allowExt parameter to bypass file type restrictions and upload executable files like PHP shells to the web root.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Puntuación base: 9.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.40%
Percentil entre todas las CVEs puntuadas: 32
Fecha de la puntuación: 6/10/2026

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).

🎯 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 principalT1505.003 Web Shellpersistence90 %

Vulnerabilidad en plugin WordPress accesible sin autenticación (AV:N, PR:N, UI:N). Permite subida arbitraria de ficheros PHP a raíz web para crear web shell; explotación remota directa (T1190). La capacidad de ejecutar código PHP en el servidor es el impacto principal (T1505.003).

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

Vulnerability Scanning User Account Management Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Download From Files — Download From Files^AI

CWE

CWE-306

Referencias

JSON original (NVD)

Mostrar

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