You can find Plone CMS applications using this tool.
Plone is a mature, secure and user-friendly Content Management System (CMS). Plone - and the Open Source community behind it - aggregates more than 15 years experience in content management. It offers all major features expected by a modern CMS out-of-the-box. Lots of customizations can be made trough-the-web, such as creating content types, themes, workflows and much more. Pushed one step further Plone can be used as a framework on which to build custom CMS-like solutions.
If attackers detect the technology used, they will try to detect vulnerabilities related to this application.
Only use components that do not have known vulnerabilities, only use components that when combined to not introduce a security vulnerability, and ensure that a misconfiguration does not cause any vulnerabilities.