ModifyUserParse.js

//REQUIRE PARSE
var Parse = require('parse').Parse;

//ADD NECESSARY KEYS - FOR MODIFY IS NECESSARY MASTER KEY
Parse.initialize(APP_KEY, JSC_KEY, MASTER_KEY);

//YOU HAVE USE THIS COMMAND FOR USE MASTER KEY
Parse.Cloud.useMasterKey();

var UserClass = Parse.Object.extend('_User');
var user = new UserClass();
user.id = "K0yi1UZpG8";
user.set('name','John');

user.save(null,{
	success: function(person) {
		console.log("modify");
	}, error : function(person, error) {
		console.log(error);
	}
});