diff --git a/file/lib/data/message/Message.class.php b/file/lib/data/message/Message.class.php
index ccceb0c..809ea20 100644
--- a/file/lib/data/message/Message.class.php
+++ b/file/lib/data/message/Message.class.php
@@ -128,7 +128,7 @@ public function getUsername($colored = false) {
 				$username = \chat\util\ChatUtil::gradient($username, $this->color1, $this->color2);
 			}
 			else {
-				$username = '<span class="defaultColor">'.$username.'</span>';
+				$username = '<span class="defaultColor">'.\wcf\util\StringUtil::encodeHTML($username).'</span>';
 			}
 		}