diff --git a/core/modules/file/src/Plugin/Validation/Constraint/FileValidationConstraintValidator.php b/core/modules/file/src/Plugin/Validation/Constraint/FileValidationConstraintValidator.php
index 2c8d8ddf67..cc7a17def8 100644
--- a/core/modules/file/src/Plugin/Validation/Constraint/FileValidationConstraintValidator.php
+++ b/core/modules/file/src/Plugin/Validation/Constraint/FileValidationConstraintValidator.php
@@ -26,8 +26,9 @@ public function validate($value, Constraint $constraint) {
     $validators = $value->getUploadValidators();
 
     // Always respect the configured maximum file size.
-    if ($max_filesize = Bytes::toInt($value->getFieldDefinition()->getSetting('max_filesize'))) {
-      $validators['file_validate_size'] = [$max_filesize];
+    $field_settings = $value->getFieldDefinition()->getSettings();
+    if (array_key_exists('max_filesize', $field_settings)) {
+      $validators['file_validate_size'] = [Bytes::toNumber($field_settings['max_filesize'])];
     }
     else {
       // Do not validate the file size if it is not set explicitly.