Widget Settings Importer/Exporter Plugin <= 1.5.3 - Unauthorized Widget Import to Stored Cross-Site Scripting

The Widget Settings Importer/Exporter Plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the wp_ajax_import_widget_dataparameter AJAX action in versions up to, and including, 1.5.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers with subscriber-level permissions and above to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.