diff -u b/core/includes/install.core.inc b/core/includes/install.core.inc
--- b/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -1184,7 +1184,7 @@
       'required' => TRUE,
     );
     $settings['drupal_hash_salt'] = (object) array(
-      'value'    => drupal_hash_base64(drupal_random_bytes(55)),
+      'value'    => Crypt::randomStringHashed(55),
       'required' => TRUE,
     );
   }