diff --git a/files/lib/data/command/CommandCache.class.php b/files/lib/data/command/CommandCache.class.php
index 5c31820..0d1522b 100644
--- a/files/lib/data/command/CommandCache.class.php
+++ b/files/lib/data/command/CommandCache.class.php
@@ -22,7 +22,7 @@
 /**
  * Manages the command cache.
  */
-class CommandCache extends SingletonFactory
+final class CommandCache extends SingletonFactory
 {
     /**
      * list of cached commands