Fix an XSS vulnerability
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 3ae2341..ad7d6a4 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -7,6 +7,10 @@
 
 Release Date: Not Released
 
+-  **Security**
+
+   -  Fixed an XSS vulnerability in :doc:`Security Library <libraries/security>` method ``xss_clean()``.
+
 -  General Changes
 
    -  Deprecated ``$config['allow_get_array']``.