CVE-2024-31465: XWiki Platform: Remote code execution from account via SearchSuggestSourceSheet

Any user with edit right on any page can execute any code on the server by adding an object of type XWiki.SearchSuggestSourceClass to their user profile or any other page. This compromises the confidentiality, integrity and availability of the whole XWiki installation.

To reproduce on an instance, as a user without script nor programming rights, add an object of type XWiki.SearchSuggestSourceClass to your profile page. On this object, set every possible property to }}}{{async}}{{groovy}}println("Hello from Groovy!"){{/groovy}}{{/async}} (i.e., name, engine, service, query, limit and icon). Save and display the page, then append ?sheet=XWiki.SearchSuggestSourceSheet to the URL. If any property displays as Hello from Groovy!}}}, then the instance is vulnerable.