Passing a $_GET variable from Wordpress page into external iFrame

Question

I have searched throughout all of the internets to fix this issue - I am sure this can be done! I am trying to pass a $_GET variable into an external page that is accessed through an iframe. My website is done on Wordpress and I have downloaded a plugin to use an iframe so that I can show a page that contains PHP. This is the way it works:

The page on Wordpress should have a $_GET parameter in its URL (like this: http://www.url.com/page/refer-a-friend/?source=CRM)

I need to access this $_GET parameter inside my iframe. The iframe src is a page I do not have on Wordpress but that is on my server (it's like an external link).

I feel like I have given all the information I can but if not please feel free to ask and I can elaborate. It's driving me crazy! Thanks.

Please note I am passing the iFrame through the shortcode. [iframe src="https://www.globaleye.com/external/refer.php" width="100%" height="500"]

Answer 1

Edit:

[iframe src="globaleye.com/external/refer.php?YOUR_VARIABLE=true"; width="100%" height="500"]

if you used more than one variable pass so you use an advanced iframe plugin so it is good for you.

[advanced_iframe securitykey="key" url_forward_parameter="SECOND_VARIABLE" src="globaleye.com/external/refer.php?YOUR_VARIABLE=true"]