diff --git a/app/pages/security.php b/app/pages/security.php
index 6ebf9ab..95f4a28 100644
--- a/app/pages/security.php
+++ b/app/pages/security.php
@@ -9,9 +9,9 @@ if (!($userObject->hasRight($user_id, 'superuser') ||
     exit;
 }
 
-if (!isset($currentUser)) {
-    include '../app/templates/error-unauthorized.php';
-    exit;
+if (!Session::getUsername()) {
+    header('Location: ' . htmlspecialchars($app_root) . '?page=login');
+    exit();
 }
 
 // Get current section
diff --git a/app/templates/page-footer.php b/app/templates/page-footer.php
index 3b126aa..9e7c076 100644
--- a/app/templates/page-footer.php
+++ b/app/templates/page-footer.php
@@ -12,7 +12,7 @@
 
     </div>
 
-<?php if (isset($currentUser) && $page !== 'logout') { ?>
+<?php if (Session::getUsername() && $page !== 'logout') { ?>
     <script src="static/js/sidebar.js"></script>
 <?php } ?>
 
diff --git a/app/templates/page-header.php b/app/templates/page-header.php
index 1d09c26..b57da5c 100644
--- a/app/templates/page-header.php
+++ b/app/templates/page-header.php
@@ -10,7 +10,7 @@
     <link rel="stylesheet" type="text/css" href="<?= htmlspecialchars($app_root) ?>static/css/main.css">
     <link rel="stylesheet" type="text/css" href="<?= htmlspecialchars($app_root) ?>static/css/messages.css">
     <script src="<?= htmlspecialchars($app_root) ?>static/js/messages.js"></script>
-<?php  if (isset($currentUser)) { ?>
+<?php  if (Session::getUsername()) { ?>
     <script>
     // restore sidebar state before the page is rendered
         (function () {