An issue was discovered in PONTON X/P Messenger before 3.11.2. The navigation tree that is shown on the left side of every page of the web application is vulnerable to XSS: it allows injection of JavaScript into its nodes. Creating such nodes is only possible for users who have the role Configuration Administrator or Administrator.
https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2021-079.txt