PHP tags in URL

So I made a landing page for all these forms that the marketing department at my work makes. One of the fields they pass is a URL that I redirect to after I'm done processing - a thank you page.

Recently, I discovered a URL that looked like this:

http://www.oursite.com/folder/thank-you.php?thankyou=free-guide&amp;adgroup=<?php echo nfpa-c ?>&amp;reference=<?php echo  ?>

Does this amount to anything but the form creator being dumb? My page is throwing huge errors about security and cross-site scripting, etc. What are the implications of this? Is there any legitimate reason to do this?

EDIT/UPDATE: My landing开发者_如何学C page is in ASP.NET. The error it mentions is possible cross-site scripting.

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<?php echo nfpa-c ?

I don't think it's the poster being dumb - this looks more like an outgoing form was not setup properly (e.g. PHP instructions used in a .html page that doesn't get parsed by the PHP interpreter.)

Check out the originating forms and look into their source code.

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There is no legitimate reason to pass PHP code on the url like this. In fact it would be a Remote Code Execution Vulnerability, which is as bad as it gets its like like saying "Check Mate". I would make sure that that you don't have this code running, although its likely a bug because in php they would use eval("echo 'nfpa-c'");, you can't eval php tags like that, so its probably untested code.