diff --git a/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js b/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js
index e9251729317ddde18e9408d8b6f3f924ea044fc1..41c7f09f04a8ef3d69e8e7ffde27687c7c85783d 100644
--- a/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js
+++ b/typo3/sysext/backend/Resources/Public/JavaScript/FormEngineValidation.js
@@ -237,7 +237,7 @@ define(['jquery', 'TYPO3/CMS/Backend/FormEngine'], function ($, FormEngine) {
 	 * @returns {String}
 	 */
 	FormEngineValidation.validateField = function($field, value) {
-		value = value || $field.val();
+		value = value || $field.val() || '';
 
 		var rules = $field.data('formengine-validation-rules');
 		var markParent = false;