SureForms <= 1.13.1 - Missing Authorization to Unauthenticated Sensitive Information Exposure

The SureForms plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 1.13.1 via the '_srfm_email_notification' post meta registration. This is due to setting the 'auth_callback' parameter to '__return_true', which allows unauthenticated access to the metadata. This makes it possible for unauthenticated attackers to extract sensitive data including email notification configurations, which frequently contain vendor-provided CRM/help desk dropbox addresses, CC/BCC recipients, and notification templates that can be abused to inject malicious data into downstream systems.