diff --git a/lib/process-services/src/lib/form/widgets/content-widget/attach-file-widget.component.ts b/lib/process-services/src/lib/form/widgets/content-widget/attach-file-widget.component.ts
index 0473d03912..7eb90c6caf 100644
--- a/lib/process-services/src/lib/form/widgets/content-widget/attach-file-widget.component.ts
+++ b/lib/process-services/src/lib/form/widgets/content-widget/attach-file-widget.component.ts
@@ -283,7 +283,7 @@ export class AttachFileWidgetComponent extends UploadWidgetComponent implements
     }
 
     private getDomainHost(urlToCheck: string): string {
-        const result = urlToCheck.match('^(?:https?:\/\/)?(?:[^@\/\n]+@)?(?:www\.)?([^:\/?\n]+)');
+        const result = urlToCheck.match('^(?:https?:\/\/)?(?:[^@\/\n]+@)?(?:www\\.)?([^:\/?\n]+)');
         return result[1];
     }