Merge upstream
diff --git a/system/core/Config.php b/system/core/Config.php
index 6636911..6841743 100755
--- a/system/core/Config.php
+++ b/system/core/Config.php
@@ -80,7 +80,7 @@
 		{
 			if (isset($_SERVER['HTTP_HOST']))
 			{
-				$base_url = isset($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) !== 'off' ? 'https' : 'http';
+				$base_url = ! empty($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) !== 'off' ? 'https' : 'http';
 				$base_url .= '://'. $_SERVER['HTTP_HOST']
 					. str_replace(basename($_SERVER['SCRIPT_NAME']), '', $_SERVER['SCRIPT_NAME']);
 			}
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index fcf6612..82caa5a 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -104,6 +104,7 @@
 -  In Pagination library, when use_page_numbers=TRUE previous link and page 1 link do not have the same url
 -  Fixed a bug (#561) - Errors in :doc:`XML-RPC Library <libraries/xmlrpc>` were not properly escaped.
 -  Fixed a bug (#904) - ``CI_Loader::initialize()`` caused a PHP Fatal error to be triggered if error level E_STRICT is used.
+-  Fixed a hosting edge case where an empty $_SERVER['HTTPS'] variable would evaluate to 'on'
 -  Fixed a bug in the Oracle (oci8) instance of :doc:`Database Forge Class <database/forge>` where ``create_table()`` would fail if used with ``AUTO_INCREMENT`` as it's not supported by Oracle.
 -  Fixed a bug (#413) - The Oracle (oci8) database driver only used to return connection-related errors in `_error_message()` and `_error_number()`.