diff --git a/controller/upload_file.rst b/controller/upload_file.rst
index b3dc2d6ffd0..425709be0d2 100644
--- a/controller/upload_file.rst
+++ b/controller/upload_file.rst
@@ -77,11 +77,8 @@ so Symfony doesn't try to get/set its value from the related entity::
                     'constraints' => [
                         new File([
                             'maxSize' => '1024k',
-                            'mimeTypes' => [
-                                'application/pdf',
-                                'application/x-pdf',
-                            ],
-                            'mimeTypesMessage' => 'Please upload a valid PDF document',
+                            'extensions' => ['pdf'],
+                            'extensionsMessage' => 'Please upload a valid PDF document',
                         ])
                     ],
                 ])