diff --git a/core/modules/dblog/src/Controller/DbLogController.php b/core/modules/dblog/src/Controller/DbLogController.php
index 2331f78..83764c4 100644
--- a/core/modules/dblog/src/Controller/DbLogController.php
+++ b/core/modules/dblog/src/Controller/DbLogController.php
@@ -248,6 +248,15 @@ public function eventDetails($event_id) {
       else {
         $event_link = SafeMarkup::set($dblog->link);
       }
+
+      // Validate the message if it is safe.
+      if (!SafeMarkup::isSafe($message)) {
+        $message = Xss::filterAdmin($message);
+      }
+      else {
+        $message = SafeMarkup::set($message);
+      }
+
       $rows = array(
         array(
           array('data' => $this->t('Type'), 'header' => TRUE),