XWiki Platform is a generic wiki platform. Starting in version 5.0-rc-1 and prior to versions 14.10.20, 15.5.4, and 15.9-rc-1, 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. This vulnerability has been patched in XWiki 14.10.20, 15.5.4 and 15.10 RC1. As a workaround, manually apply the patch to the document `XWiki.SearchSuggestSourceSheet`.
https://jira.xwiki.org/browse/XWIKI-21474
https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-34fj-r5gq-7395
https://github.com/xwiki/xwiki-platform/commit/6a7f19f6424036fce3d703413137adde950ae809
https://github.com/xwiki/xwiki-platform/commit/2740974c32dbb7cc565546d0f04e2374b32b36f7
https://github.com/xwiki/xwiki-platform/commit/0317a3aa78065e66c86fc725976b06bf7f9b446e