diff --git a/lib/default.php b/lib/default.php
index 466bd26fff..2e681e34b1 100644
--- a/lib/default.php
+++ b/lib/default.php
@@ -128,7 +128,7 @@ $default =
         array('banned' => array(),
               'biolimit' => null,
               'changenick' => false,
-              'backup' => true,
+              'backup' => false,    // can cause DoS, so should be done via CLI
               'restore' => false,
               'delete' => false,
               'move' => true),