diff --git a/core/modules/system/src/Tests/Installer/InstallerExistingSettingsNoProfileTest.php b/core/modules/system/src/Tests/Installer/InstallerExistingSettingsNoProfileTest.php
index 9e97b38..1b915d5 100644
--- a/core/modules/system/src/Tests/Installer/InstallerExistingSettingsNoProfileTest.php
+++ b/core/modules/system/src/Tests/Installer/InstallerExistingSettingsNoProfileTest.php
@@ -7,9 +7,11 @@
 
 namespace Drupal\system\Tests\Installer;
 
+use Drupal\Core\DrupalKernel;
 use Drupal\Core\Site\Settings;
 use Drupal\simpletest\InstallerTestBase;
 use Drupal\Core\Database\Database;
+use Symfony\Component\HttpFoundation\Request;
 
 /**
  * Tests the installer with an existing settings file but no install profile.
@@ -45,7 +47,7 @@ protected function setUp() {
     // Pre-configure config directories.
     $this->settings['config_directories'] = array(
       CONFIG_STAGING_DIRECTORY => (object) array(
-        'value' => conf_path() . '/files/config_staging',
+        'value' => DrupalKernel::findSitePath(Request::createFromGlobals()) . '/files/config_staging',
         'required' => TRUE,
       ),
     );