How to hide password in the nodejs console?

This can be handled with readline by intercepting the output through a muted stream, as is done in the read project on npm (https://github.com/isaacs/read/blob/master/lib/read.js):

var readline = require('readline');
var Writable = require('stream').Writable;

var mutableStdout = new Writable({
  write: function(chunk, encoding, callback) {
    if (!this.muted)
      process.stdout.write(chunk, encoding);
    callback();
  }
});

mutableStdout.muted = false;

var rl = readline.createInterface({
  input: process.stdin,
  output: mutableStdout,
  terminal: true
});

rl.question('Password: ', function(password) {
  console.log('\nPassword is ' + password);
  rl.close();
});

mutableStdout.muted = true;