diff --git src/wp-includes/class-wp.php src/wp-includes/class-wp.php
index 28e7474..2027b68 100644
--- src/wp-includes/class-wp.php
+++ src/wp-includes/class-wp.php
@@ -662,7 +662,7 @@ class WP {
 
 				// Only set X-Pingback for single posts that allow pings.
 				if ( $p && pings_open( $p ) ) {
-					@header( 'X-Pingback: ' . get_bloginfo( 'pingback_url' ) );
+					@header( 'X-Pingback: ' . get_bloginfo( 'pingback_url', 'display' ) );
 				}
 
 				// check for paged content that exceeds the max number of pages