passing directly username and password to external site in iframe

Question

I want to have a form on our main member page that they can submit on, and then I want to pass the username and password to the service which will be embedded in an iframe on our site to allow a seamless login.

Answer 1

Sorry, this won't work with the browser's security model for iframes. Methods for getting around this (i.e. pushing data into the name of a window) exist, but would be terrible for passing secret information like a password.

A real solution here will require something like the embedded site authenticating the user independently. OpenID could help you, here.

Answer 2

Passing secret information this way is really dangerous, do consider other options as this one will harm your users a lot.