The RSS subsystem in ILIAS 5.1.x, 5.2.x, and 5.3.x before 5.3.5 has XSS via a URI to Services/Feeds/classes/class.ilExternalFeedItem.php.

References

• advisory https://www.ilias.de/docu/goto.php?target=st_229
• patch https://github.com/ILIAS-eLearning/ILIAS/commit/6b2217c31b6974788a5c787413454475687b44bb
• patch https://github.com/ILIAS-eLearning/ILIAS/commit/d0dcad1b1e729f694acd0582bc626c7c8e62b519