There is no such thing, but the standard dictates that all payment pages have to be served from a PCI DSS compliant environment. Stripe is in a very grey area,

There is no such thing, but the standard dictates that all payment pages have to be served from a PCI DSS compliant environment. Stripe is in a very grey area, because they don't even have their merchants use iframes. Tampering with the script that (according to Stripe) makes the merchant compliant, and not being certified doing so, is a big no-no.