[ci skip] Fix a bug in FV valid_email()
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 362cd8c..4695edc 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -7,6 +7,10 @@
Release Date: Not Released
+- **Security**
+
+ - :doc:`Form Validation Library <libraries/form_validation>` rule ``valid_email`` could be bypassed if ``idn_to_ascii()`` is available.
+
- General Changes
- Updated :doc:`Form Helper <helpers/form_helper>` function :php:func:`form_label()` to accept HTML attributes as a string.