Index: wp-includes/category-template.php
===================================================================
--- wp-includes/category-template.php	(revision 12456)
+++ wp-includes/category-template.php	(working copy)
@@ -456,6 +456,8 @@
 	extract( $r );
 
 	$categories = get_categories( $r );
+	$name = esc_attr($name);
+	$class = esc_attr($class);
 
 	$output = '';
 	if ( $title_li && 'list' == $style )