CVE-2021-4455

Status: DeferredCritical (9.8)—

The Wordpress Plugin Smart Product Review plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in all versions up to, and including, 1.0.4. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Base score: 9.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.79%
Percentile among all scored CVEs: 55
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 Shellpersistence95 %
Secondary impactT1059 Command and Scripting Interpreterexecution85 %

AV:N/PR:N/UI:N permite explotación remota sin autenticación (T1190). Carga de archivos arbitrarios sin validación en plugin WordPress puede desplegar web shell (T1505.003) y ejecutar código (T1059).

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

Privileged Account Management Disable or Remove Feature or Program Vulnerability Scanning User Account Management Restrict Web-Based Content Network Segmentation

Affected technologies (1)

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

Smart Product Review — Smart Product Review^AI

CWEs

CWE-434

References

Raw JSON (NVD)

Show

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          "options": [
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          "version": "2.0.3",
          "timestamp": "2025-04-21T14:14:11.030861Z"
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  "published": "2025-04-19T08:15:13.220",
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      "url": "https://www.exploit-db.com/exploits/50533",
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      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/1de9183c-95b9-4500-85e2-08dcee956360?source=cve",
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    }
  ],
  "lastModified": "2026-06-17T04:19:47.597",
  "sourceIdentifier": "security@wordfence.com"
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