diff --git a/modules/upload/upload.module b/modules/upload/upload.module
index 26a46e74b56485f8d70ab801dc2f16c67d8138dd..68bf09d23dedad66b6df705abad11279e194efa5 100644
--- a/modules/upload/upload.module
+++ b/modules/upload/upload.module
@@ -279,7 +279,8 @@ function upload_file_download($file) {
         return array(
           'Content-Type: '. $type .'; name='. $name,
           'Content-Length: '. $file->filesize,
-          'Content-Disposition: '. $disposition .'; filename='. $name
+          'Content-Disposition: '. $disposition .'; filename='. $name,
+          'Cache-Control: private'
         );
       }
       else {