Drag and Drop Multiple File Upload for Contact Form 7 < 1.3.9.9 - Unauthenticated RCE via Control Character Filename Bypass

Description

The plugin does not validate the final name of an uploaded file after stripping characters from it, allowing unauthenticated users to defeat its file type restrictions and execute arbitrary code on the server.

Exploitation requires a non-default field configuration on one of the site's forms, and a web server that honours per-directory configuration overrides.