SurveyJS: Drag & Drop WordPress Form Builder to create, style and embed multiple forms of any complexity <= 2.5.2 - Cross-Site Request Forgery to Survey Cloning

The SurveyJS: Drag & Drop WordPress Form Builder to create, style and embed multiple forms of any complexity plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 2.5.2. This is due to missing or incorrect nonce validation on the `SurveyJS_CloneSurvey` AJAX action. This makes it possible for unauthenticated attackers to duplicate surveys via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.