Is There a Way to Completely Turn Off Pingbacks/Trackbacks?

Question

There is the option to turn off trackbacks/pingbacks under Settings > Discussion.

But I'd like remove the X-Pingback header WordPress sends and completely remove the the trackback endpoint.

Is there a way to do this?

Answer 1

<?php
/*
Plugin Name: [RPC] XMLRPCless Blog
Plugin URI: http://earnestodev.com/
Description: Disable XMLRPC advertising/functionality blog-wide.
Version: 0.0.7
Author: EarnestoDev
Author URI: http://earnestodev.com/
*/
// Disable X-Pingback HTTP Header.
add_filter('wp_headers', function($headers, $wp_query){
    if(isset($headers['X-Pingback'])){
        // Drop X-Pingback
        unset($headers['X-Pingback']);
    }
    return $headers;
}, 11, 2);
// Disable XMLRPC by hijacking and blocking the option.
add_filter('pre_option_enable_xmlrpc', function($state){
    return '0'; // return $state; // To leave XMLRPC intact and drop just Pingback
});
// Remove rsd_link from filters (<link rel="EditURI" />).
add_action('wp', function(){
    remove_action('wp_head', 'rsd_link');
}, 9);
// Hijack pingback_url for get_bloginfo (<link rel="pingback" />).
add_filter('bloginfo_url', function($output, $property){
    return ($property == 'pingback_url') ? null : $output;
}, 11, 2);
// Just disable pingback.ping functionality while leaving XMLRPC intact?
add_action('xmlrpc_call', function($method){
    if($method != 'pingback.ping') return;
    wp_die(
        'Pingback functionality is disabled on this Blog.',
        'Pingback Disabled!',
        array('response' => 403)
    );
});
?>

Use this for a plugin in /wp-content/plugins or /wp-content/mu-plugins (for auto-activation). Or functions.php.

Answer 2

@EarnestoDev had a great answer, but it's a little outdated now since recent xml-rcp exploits.

I've made an updated version that I think blocks all possible access to it. Take note though that there are a few plugins out there that utilize the XML-RPC pingback/trackback functionality and could have issues if you are using them:

• WordPress Mobile App
• JetPack LibSyn (for podcasts)
• Some parts of BuddyPress
• Windows Live Writer
• IFTTT
• A few gallery plugins

---

Here's an updated version below. To download it you can copy it into a plugin file, drop in in mu-plugins or download it on github:

<?php
/*
Plugin Name:        BYE BYE Pingback
Plugin URI:         https://github.com/Wordpress-Development/bye-bye-pingback/
Description:        Banishment of wordpress pingback
Version:            1.0.0
Author:             bryanwillis
Author URI:         https://github.com/bryanwillis/
*/

// If this file is called directly, abort.
if ( ! defined( 'WPINC' ) ) {
    die;
}

/**
 * Htaccess directive block xmlrcp for extra security.
 * Here are some rewrite examples:
 *   404 - RewriteRule xmlrpc\.php$ - [R=404,L]
 *   301 - RewriteRule ^xmlrpc\.php$ index.php [R=301]
 * If you want custom 404 make sure your server is finding it by also adding this 'ErrorDocument 404 /index.php?error=404' or 'ErrorDocument 404 /wordpress/index.php?error=404' for sites in subdirectory.
 */ 
add_filter('mod_rewrite_rules', 'noxmlrpc_mod_rewrite_rules'); // should we put this inside wp_loaded or activation hook
function noxmlrpc_mod_rewrite_rules($rules) {
  $insert = "RewriteRule xmlrpc\.php$ - [F,L]";
  $rules = preg_replace('!RewriteRule!', "$insert\n\nRewriteRule", $rules, 1);
  return $rules;
}

register_activation_hook(__FILE__, 'noxmlrpc_htaccess_activate');
function noxmlrpc_htaccess_activate() {
  flush_rewrite_rules(true);
}

register_deactivation_hook(__FILE__, 'noxmlrpc_htaccess_deactivate');
function noxmlrpc_htaccess_deactivate() {
  remove_filter('mod_rewrite_rules', 'noxmlrpc_mod_rewrite_rules');
  flush_rewrite_rules(true);
}


// Remove rsd_link from filters- link rel="EditURI"
add_action('wp', function(){
    remove_action('wp_head', 'rsd_link');
}, 9);


// Remove pingback from head (link rel="pingback")
if (!is_admin()) {      
    function link_rel_buffer_callback($buffer) {
        $buffer = preg_replace('/(<link.*?rel=("|\')pingback("|\').*?href=("|\')(.*?)("|\')(.*?)?\/?>|<link.*?href=("|\')(.*?)("|\').*?rel=("|\')pingback("|\')(.*?)?\/?>)/i', '', $buffer);
                return $buffer;
    }
    function link_rel_buffer_start() {
        ob_start("link_rel_buffer_callback");
    }
    function link_rel_buffer_end() {
        ob_flush();
    }
    add_action('template_redirect', 'link_rel_buffer_start', -1);
    add_action('get_header', 'link_rel_buffer_start');
    add_action('wp_head', 'link_rel_buffer_end', 999);
}


// Return pingback_url empty (<link rel="pingback" href>).
add_filter('bloginfo_url', function($output, $property){
    return ($property == 'pingback_url') ? null : $output;
}, 11, 2);


// Disable xmlrcp/pingback
add_filter( 'xmlrpc_enabled', '__return_false' );
add_filter( 'pre_update_option_enable_xmlrpc', '__return_false' );
add_filter( 'pre_option_enable_xmlrpc', '__return_zero' );

// Disable trackbacks
add_filter( 'rewrite_rules_array', function( $rules ) {
    foreach( $rules as $rule => $rewrite ) {
        if( preg_match( '/trackback\/\?\$$/i', $rule ) ) {
            unset( $rules[$rule] );
        }
    }
    return $rules;
});


// Disable X-Pingback HTTP Header.
add_filter('wp_headers', function($headers, $wp_query){
    if(isset($headers['X-Pingback'])){
        unset($headers['X-Pingback']);
    }
    return $headers;
}, 11, 2);


add_filter( 'xmlrpc_methods', function($methods){
    unset( $methods['pingback.ping'] );
    unset( $methods['pingback.extensions.getPingbacks'] );
    unset( $methods['wp.getUsersBlogs'] ); // Block brute force discovery of existing users
    unset( $methods['system.multicall'] );
    unset( $methods['system.listMethods'] );
    unset( $methods['system.getCapabilities'] );
    return $methods;
});


// Just disable pingback.ping functionality while leaving XMLRPC intact?
add_action('xmlrpc_call', function($method){
    if($method != 'pingback.ping') return;
    wp_die(
        'This site does not have pingback.',
        'Pingback not Enabled!',
        array('response' => 403)
    );
});

---

Also, if you want to close all existing pingback follow these steps:

1) Open phpmyadmin and navigate to SQL section:

2) Enter the following:

UPDATE wp_posts SET ping_status="closed";

3) All existing pingbacks should now be closed