Index: wp-includes/default-filters.php
===================================================================
--- wp-includes/default-filters.php	(revision 15448)
+++ wp-includes/default-filters.php	(working copy)
@@ -113,6 +113,7 @@
 add_filter( 'the_title', 'wptexturize'   );
 add_filter( 'the_title', 'convert_chars' );
 add_filter( 'the_title', 'trim'          );
+add_filter( 'the_title', 'esc_html'      );
 
 add_filter( 'the_content', 'wptexturize'        );
 add_filter( 'the_content', 'convert_smilies'    );