diff --git a/core/lib/Drupal/Core/PhpStorage/PhpStorageFactory.php b/core/lib/Drupal/Core/PhpStorage/PhpStorageFactory.php
index 5ca0971..575e660 100644
--- a/core/lib/Drupal/Core/PhpStorage/PhpStorageFactory.php
+++ b/core/lib/Drupal/Core/PhpStorage/PhpStorageFactory.php
@@ -34,6 +34,7 @@ class PhpStorageFactory {
    *   An instantiated storage for the specified name.
    */
   static function get($name) {
+    $configuration = array();
     $overrides = Settings::get('php_storage');
     if (isset($overrides[$name])) {
       $configuration = $overrides[$name];
@@ -41,13 +42,11 @@ static function get($name) {
     elseif (isset($overrides['default'])) {
       $configuration = $overrides['default'];
     }
-    else {
-      $configuration = array(
-        'class' => 'Drupal\Component\PhpStorage\MTimeProtectedFileStorage',
-        'secret' => Settings::getHashSalt(),
-      );
-    }
+    // Make sure all the necessary configuration values are set.
     $class = isset($configuration['class']) ? $configuration['class'] : 'Drupal\Component\PhpStorage\MTimeProtectedFileStorage';
+    if (!isset($configuration['secret'])) {
+      $configuration['secret'] = Settings::getHashSalt();
+    }
     if (!isset($configuration['bin'])) {
       $configuration['bin'] = $name;
     }
diff --git a/core/modules/system/tests/src/Kernel/PhpStorage/PhpStorageFactoryTest.php b/core/modules/system/tests/src/Kernel/PhpStorage/PhpStorageFactoryTest.php
index 47804ab..cdd451a 100644
--- a/core/modules/system/tests/src/Kernel/PhpStorage/PhpStorageFactoryTest.php
+++ b/core/modules/system/tests/src/Kernel/PhpStorage/PhpStorageFactoryTest.php
@@ -65,18 +65,28 @@ public function testGetOverride() {
     $this->setSettings('test', array('bin' => NULL));
     $php = PhpStorageFactory::get('test');
     $this->assertTrue($php instanceof MockPhpStorage, 'An MockPhpStorage instance was returned from overridden settings.');
-    $this->assertIdentical('test', $php->getConfigurationValue('bin'), 'Name value was used for bin.');
+    $this->assertSame('test', $php->getConfigurationValue('bin'), 'Name value was used for bin.');
 
     // Test that a default directory is set if it's empty.
     $this->setSettings('test', array('directory' => NULL));
     $php = PhpStorageFactory::get('test');
     $this->assertTrue($php instanceof MockPhpStorage, 'An MockPhpStorage instance was returned from overridden settings.');
-    $this->assertIdentical(PublicStream::basePath() . '/php', $php->getConfigurationValue('directory'), 'Default file directory was used.');
+    $this->assertSame(PublicStream::basePath() . '/php', $php->getConfigurationValue('directory'), 'Default file directory was used.');
 
     // Test that a default storage class is set if it's empty.
     $this->setSettings('test', array('class' => NULL));
     $php = PhpStorageFactory::get('test');
     $this->assertTrue($php instanceof MTimeProtectedFileStorage, 'An MTimeProtectedFileStorage instance was returned from overridden settings with no class.');
+
+    // Test that a default secret is not returned if it's set in the override.
+    $this->setSettings('test');
+    $php = PhpStorageFactory::get('test');
+    $this->assertNotEquals('mock hash salt', $php->getConfigurationValue('secret'), 'The default secret is used if one is not set in the overridden settings.');
+
+    // Test that a default secret is set if it's empty.
+    $this->setSettings('test', array('secret' => NULL));
+    $php = PhpStorageFactory::get('test');
+    $this->assertSame('mock hash salt', $php->getConfigurationValue('secret'), 'The default secret is used if one is not set in the overridden settings.');
   }
 
   /**
@@ -94,6 +104,7 @@ protected function setSettings($name = 'default', array $configuration = array()
       'secret' => $this->randomString(),
       'bin' => 'test',
     );
+    $settings['hash_salt'] = 'mock hash salt';
     new Settings($settings);
   }