diff --git a/wp-includes/rest-api.php b/wp-includes/rest-api.php
index ad9bf62b2e..980f4c72a3 100644
--- a/wp-includes/rest-api.php
+++ b/wp-includes/rest-api.php
@@ -256,7 +256,11 @@ function rest_api_loaded() {
 	$server = rest_get_server();
 
 	// Fire off the request.
-	$server->serve_request( untrailingslashit( $GLOBALS['wp']->query_vars['rest_route'] ) );
+	$route = untrailingslashit( $GLOBALS['wp']->query_vars['rest_route'] );
+	if ( empty( $route ) ) {
+		$route = '/';
+	}
+	$server->serve_request( $route );
 
 	// We're done.
 	die();
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 6a0d0539ef..5a29929e1d 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-39922';
+$wp_version = '4.8-alpha-39923';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.