CVE-2026-4883
CriticalSummary
The Piotnet Forms plugin for WordPress is vulnerable to arbitrary file upload due to missing file type validation in the 'piotnetforms_ajax_form_builder' function in all versions up to and including 2.1.40. The plugin uses an incomplete extension blacklist, allowing dangerous file uploads.
Risk Assessment
Unauthenticated attackers can upload arbitrary files to the affected site's server, potentially leading to remote code execution. This poses a significant security risk to the system.
Recommendation
It is recommended to update the Piotnet Forms plugin to the latest version to mitigate this vulnerability. Additionally, implementing further security measures, such as restricting allowed file types, is advisable.
Original NVD description (English source)
The Piotnet Forms plugin for WordPress is vulnerable to arbitrary file upload due to missing file type validation in the 'piotnetforms_ajax_form_builder' function in all versions up to, and including, 2.1.40. The plugin uses an incomplete extension blacklist that only blocks php, phpt, php5, php7, and exe extensions, while allowing dangerous extensions such as .phar or .phtml to be uploaded. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible. Note: The exploit can only be exploited if a file field is added to the form.