{"id":55505,"date":"2026-05-19T08:17:17","date_gmt":"2026-05-19T08:17:17","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=55505"},"modified":"2026-05-19T08:17:17","modified_gmt":"2026-05-19T08:17:17","slug":"piotnet-forms-2140-unauthenticated-arbitrary-file-upload-via-form-file-upload","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=55505","title":{"rendered":"Piotnet Forms <= 2.1.40 - Unauthenticated Arbitrary File Upload via Form File Upload_CVE-2026-4883"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;The Piotnet Forms plugin for WordPress is vulnerable to arbitrary file upload due to missing file type validation in the &#8216;piotnetforms_ajax_form_builder&#8217; 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. 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