diff --git a/src/Template.php b/src/Template.php
index 435f8c67e1..3f7447c126 100644
--- a/src/Template.php
+++ b/src/Template.php
@@ -537,7 +537,7 @@ protected function getAttribute($object, $item, array $arguments = [], $type = s
         if (self::METHOD_CALL !== $type) {
             $arrayItem = \is_bool($item) || \is_float($item) ? (int) $item : $item;
 
-            if (((\is_array($object) || $object instanceof \ArrayObject) && (isset($object[$arrayItem]) || \array_key_exists($arrayItem, $object)))
+            if (((\is_array($object) || $object instanceof \ArrayObject) && (isset($object[$arrayItem]) || \array_key_exists($arrayItem, (array) $object)))
                 || ($object instanceof \ArrayAccess && isset($object[$arrayItem]))
             ) {
                 if ($isDefinedTest) {
@@ -604,7 +604,7 @@ protected function getAttribute($object, $item, array $arguments = [], $type = s
 
         // object property
         if (self::METHOD_CALL !== $type && !$object instanceof self) { // \Twig\Template does not have public properties, and we don't want to allow access to internal ones
-            if (isset($object->$item) || \array_key_exists((string) $item, $object)) {
+            if (isset($object->$item) || \array_key_exists((string) $item, (array) $object)) {
                 if ($isDefinedTest) {
                     return true;
                 }