ILIAS before 5.1.26, 5.2.x before 5.2.15, and 5.3.x before 5.3.4, due to inconsistencies in parameter handling, is vulnerable to various instances of reflected cross-site-scripting.
https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2018-007.txt
http://www.securityfocus.com/archive/1/542025/100/0/threaded
http://packetstormsecurity.com/files/147726/ILIAS-5.3.2-5.2.14-5.1.25-Cross-Site-Scripting.html