CVE-2021-47940

Status: DeferredCritical (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

Version: 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
Base score: 9.3

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.40%
Percentile among all scored CVEs: 32
Score date: 10/6/2026

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).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access95 %
Primary impactT1505.003 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).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

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

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Download From Files — Download From Files^AI

CWEs

CWE-306

References

Raw JSON (NVD)

Show

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