diff --git a/library/Icinga/Web/Controller/AuthBackendController.php b/library/Icinga/Web/Controller/AuthBackendController.php
index 97dc4b3a9..12f8b729d 100644
--- a/library/Icinga/Web/Controller/AuthBackendController.php
+++ b/library/Icinga/Web/Controller/AuthBackendController.php
@@ -63,6 +63,7 @@ class AuthBackendController extends CompatController
      */
     protected function getUserBackend($name = null, $interface = 'Icinga\Data\Selectable')
     {
+        $backend = null;
         if ($name !== null) {
             $config = Config::app('authentication');
             if (! $config->hasSection($name)) {
@@ -121,6 +122,7 @@ class AuthBackendController extends CompatController
      */
     protected function getUserGroupBackend($name = null, $interface = 'Icinga\Data\Selectable')
     {
+        $backend = null;
         if ($name !== null) {
             $config = Config::app('groups');
             if (! $config->hasSection($name)) {