Frontend File Manager <= 18.2 - Unauthenticated HTML Injection leading to Spam Emails

Missing Authorization
CVE CVE-2021-4350
CVSS 7.2 (High)
Publicly Published July 12, 2021
Last Updated January 22, 2024
Researcher Jerome Bruandet - NinTechNet


The Frontend File Manager plugin for WordPress is vulnerable to Unauthenticated HTML Injection in versions up to, and including, 18.2. This is due to lacking authentication protections on the wpfm_send_file_in_email AJAX action. This makes it possible for unauthenticated attackers to send emails using the site with a custom subject, recipient email, and body with unsanitized HTML content. This effectively lets the attacker use the site as a spam relay.



Vulnerability Details for Frontend File Manager Plugin

Software Type Plugin
Software Slug nmedia-user-file-uploader (view on
Patched? Yes
Remediation Update to version 18.3, or a newer patched version
Affected Version
  • < 18.3
Patched Version
  • 18.3

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