The latest stable release, version 0.6.17 of Node.js has closed the hole in the HTTP implementation that would allow an attacker to exploit a small but enticing security vulnerability thus allow the would be remote attacker to access private information hosted on that server. The exploit allows the hacker to append the content of the HTTP parser buffer and spoof a request heard, thus making it appears as though the request came from a user and forwarding the contents of that request to the hacker. Read the full details of the vulnerability here.