diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index b30f585da1689f60dbb99ea2db98ee582546159b..9aa5c377b8e5888cc85fd6fd035dea8657958b48 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -82,7 +82,7 @@ class Drupal {
   /**
    * The current system version.
    */
-  const VERSION = '8.5.8';
+  const VERSION = '8.5.9';
 
   /**
    * Core API compatibility.