Look at this article as a “how-to” for testing your forms for a specific vulnerability, hijacking by inserting certain information into the header of email your form processing software sends out.

Your domain registration is critically important. It’s easy to get lazy about this stuff. Often your ISP or whoever set up your web site said they’d “take care of it” and that was it. It’s been working fine for years, and you don’t have to worry about it.

Web forms have two possible methods of passing information back to the script that will process the form. Every form will have something like this…