diff --git a/wp-includes/default-widgets.php b/wp-includes/default-widgets.php
index 100c5752c7..9b8dd6cd25 100644
--- a/wp-includes/default-widgets.php
+++ b/wp-includes/default-widgets.php
@@ -562,7 +562,7 @@ class WP_Widget_Recent_Posts extends WP_Widget {
 		<?php if ( $title ) echo $before_title . $title . $after_title; ?>
 		<ul>
 		<?php  while ($r->have_posts()) : $r->the_post(); ?>
-		<li><a href="<?php the_permalink() ?>"><?php if ( get_the_title() ) the_title(); else the_ID(); ?> </a></li>
+		<li><a href="<?php the_permalink() ?>" title="<?php echo esc_attr(get_the_title() ? get_the_title() : get_the_ID()); ?>"><?php if ( get_the_title() ) the_title(); else the_ID(); ?> </a></li>
 		<?php endwhile; ?>
 		</ul>
 		<?php echo $after_widget; ?>