WP Responsive Holiday/Events Calendar Security & Risk Analysis

The wp-responsive-holiday-events-calendar plugin v1.1.0 exhibits a mixed security posture. On the positive side, it demonstrates good practices by not using dangerous functions, performing all SQL queries using prepared statements, and having no known vulnerability history. The absence of file operations and external HTTP requests is also a positive sign. However, there are significant areas of concern primarily related to its attack surface and output sanitization. A notable issue is an unprotected AJAX handler, which represents a direct entry point for potential attackers without any authentication or authorization checks. Furthermore, a considerable portion (75%) of its output is not properly escaped, creating a high risk of Cross-Site Scripting (XSS) vulnerabilities, especially when combined with the unprotected AJAX endpoint.