CMS Made Simple (CMSMS) 2.2.15 allows authenticated XSS via the /admin/addbookmark.php script through the Site Admin > My Preferences > Title field.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-15586
http://packetstormsecurity.com/files/162287/CMS-Made-Simple-2.2.15-Cross-Site-Scripting.html