diff --git a/vendor/magento/module-reward/Block/Adminhtml/Customer/Edit/Tab/Reward/History/Grid/Column/Renderer/Reason.php b/vendor/magento/module-reward/Block/Adminhtml/Customer/Edit/Tab/Reward/History/Grid/Column/Renderer/Reason.php
index 51e8402df92a..9066b59432d2 100644
--- a/vendor/magento/module-reward/Block/Adminhtml/Customer/Edit/Tab/Reward/History/Grid/Column/Renderer/Reason.php
+++ b/vendor/magento/module-reward/Block/Adminhtml/Customer/Edit/Tab/Reward/History/Grid/Column/Renderer/Reason.php
@@ -24,6 +24,6 @@ protected function _getValue(\Magento\Framework\DataObject $row)
         if ($row->getData('is_duplicate_of') !== null) {
             $expired = '<em>' . __('Expired reward') . '</em> ';
         }
-        return $expired . parent::_getValue($row);
+        return $expired . $this->escapeHtml((string)parent::_getValue($row));
     }
 }