Port of (PHP-Bounce-Handler - https://github.com/cfortune/PHP-Bounce-Handler v7.3) in NodeJS.
var BounceHandler = require('node-bounce-handler').BounceHandler;
var bh = new BounceHandler();
var bounceResult = bh.parse_email(emlDataString);
This class can be used to parse bounced message reports. It parses e-mail messages with multipart report content type formatted according to RFC 1892 and 1894 documents. If the bounce is not well formed, it also tries to extract some useful information. Exim is supported, partially. More... http://anti-spam-man.com/php_bouncehandler/