CVE-2026-4373: JetFormBuilder <= 3.5.6.2 - Unauthenticated Arbitrary File Read via Media Field

The JetFormBuilder plugin for WordPress is vulnerable to arbitrary file read via path traversal in all versions up to, and including, 3.5.6.2. This is due to the 'Uploaded_File::set_from_array' method accepting user-supplied file paths from the Media Field preset JSON payload without validating that the path belongs to the WordPress uploads directory. Combined with an insufficient same-file check in 'File_Tools::is_same_file' that only compares basenames, this makes it possible for unauthenticated attackers to exfiltrate arbitrary local files as email attachments by submitting a crafted form request when the form is configured with a Media Field and a Send Email action with file attachment.