diff --git a/app/views/course/wizard/steps/basicdata/index_studygroup.php b/app/views/course/wizard/steps/basicdata/index_studygroup.php
index 23b87b42d8b2308ad2ba1a8c8a0925bcb618117f..d7417abd8b27017f572507e4d151b2bf068c2334 100644
--- a/app/views/course/wizard/steps/basicdata/index_studygroup.php
+++ b/app/views/course/wizard/steps/basicdata/index_studygroup.php
@@ -71,9 +71,9 @@
     <?= _('Einverstanden') ?>
 </label>
 
-<input type="hidden" name="institute" value="<?= $values['institute'] ?>"/>
-<input type="hidden" name="start_time" value="<?= $values['start_time'] ?>"/>
+<input type="hidden" name="institute" value="<?= htmlReady($values['institute']) ?>">
+<input type="hidden" name="start_time" value="<?= htmlReady($values['start_time']) ?>">
 <input type="hidden" name="studygroup" value="1"/>
 <?php foreach ($values['lecturers'] as $id => $assigned) : ?>
-    <input type="hidden" name="lecturers[<?= $id ?>]" value="1"/>
+    <input type="hidden" name="lecturers[<?= htmlReady($id) ?>]" value="1">
 <?php endforeach ?>