WordPress: Disable XML-RPC Pingbacks

The following code snippet will disable pingbacks while allowing things like Jetpack and WordPress mobile apps to function normally.
Add the code to your theme’s functions.php file:

add_filter( 'xmlrpc_methods', 'csm_remove_xmlrpc_pingback' );

function csm_remove_xmlrpc_pingback( $methods ) {
   unset( $methods['pingback.ping'] );
   return $methods;
}