CVE-2026-84750

19th percentile - higher than 19% of all known CVEs

The Ultra Addons for Contact Form 7 WordPress plugin before 3.5.51 does not validate the type or extension of files uploaded through one of its form fields, and stores them at a predictable public path with the attacker-chosen extension intact, allowing unauthenticated users to upload arbitrary files. The PHP handler shipped by default with the Debian and Ubuntu Apache packages maps .phar to PHP alongside .php and .phtml, so on that stack the uploaded file is executed and the issue leads to Remote Code Execution and full site takeover. Where the host routes only .php to the PHP handler, the same file is instead served from the site's own origin with its script intact, leading to Stored Cross-Site Scripting.

An attacker can upload a malicious file that may be executed on the server (RCE) or used to inject scripts (Stored XSS), potentially leading to full site and data compromise.

Update the plugin to version 3.5.51 or later. Additionally, configure the server to not execute files with dangerous extensions and restrict allowed file types in forms.