Path traversal in Balbooa Forms extension for Joomla

Summary

Joomla Extension - balbooa.com - Unauthenticated path traversal exfiltrates local files through auto-reply attachments in Balbooa Forms < 2.4.3.4 - Balbooa Forms accepts upload-field state as Guest-controlled JSON during public form submission. For every object whose `id` merely looks numeric, the component trusts the supplied `filename`, concatenates it below the configured upload directory, and adds the result to an array of local attachment paths. It does not load the referenced attachment row, verify ownership/session/form/field, require that the ID exists, canonicalize the path, or enforce containment. If the form's normal “auto reply” and “attach uploaded files” options are enabled, the component sends those local paths as email attachments to the address submitted in an email field. A Guest can therefore submit a nonexistent numeric ID plus a traversal filename such as `../../../../configuration.php` and receive any file readable by the Joomla process.