The Brizy Page Builder plugin <= 2.3.11 for WordPress allowed authenticated users to upload executable files to a location of their choice using the brizycreateblockscreenshot AJAX action. The file would be named using the id parameter, which could be prepended with "../" to perform directory traversal, and the file contents were populated via the ibsf parameter, which would be base64-decoded and written to the file. While the plugin added a .jpg extension to all uploaded filenames, a double extension attack was still possible, e.g. a file named shell.php would be saved as shell.php.jpg, and would be executable on a number of common configurations.

The Brizy Page Builder plugin <= 2.3.11 for WordPress used an incorrect authorization check that allowed any logged-in user accessing any endpoint in the wp-admin directory to modify the content of any existing post or page created with the Brizy editor. An identical issue was found by another researcher in Brizy <= 1.0.125 and fixed in version 1.0.126, but the vulnerability was reintroduced in version 1.0.127.

The Brizy Page Builder plugin <= 2.3.11 for WordPress was vulnerable to stored XSS by lower-privileged users such as a subscribers. It was possible to add malicious JavaScript to a page by modifying the request sent to update the page via the brizyupdateitem AJAX action and adding JavaScript to the data parameter, which would be executed in the session of any visitor viewing or previewing the post or page.