Concrete CMS before 8.5.13 and 9.x before 9.2.2 allows stored XSS on the Admin page via an uploaded file name.
https://github.com/concretecms/concretecms/pull/11739
https://github.com/concretecms/concretecms/pull/11695
https://documentation.concretecms.org/developers/introduction/version-history/922-release-notes
https://documentation.concretecms.org/developers/introduction/version-history/8513-release-notes