IE is protecting you from a dangerous misconfiguration.
It isn't appropriate to add https://*.cloudfront.net
to trusted sites, just as it would not be appropriate to add https://*.com
to trusted sites. The problem with trusting all of *.com
is obvious enough, but why CloudFront?
The reason is because anyone can have a *.cloudfront.net
subdomain. CloudFront is a service that is used by AWS customers, in addition to being used by the AWS console and even the amazon.com retail site.
But how does IE know this specific domain should be restricted? It appears to be this:
IE on the Windows 10 Technical Preview switches the parsing of domain names to use the algorithms and domain list found at http://publicsuffix.org.
https://blogs.msdn.microsoft.com/ie/2014/10/01/internet-explorer-and-the-windows-10-technical-preview/
Presumably this is still true. And, you will observe that cloudfront.net
is indeed on the public suffix list. (On the public suffix list, the absence of *
wildcards does not mean what you might assume, so the fact that the list includes cloudfront.net
but not *.cloudfront.net
is not significant, here.)
Unfortunately, it appears that you will need to identify the specific CloudFront subdomains to trust, and configure them individually.
See also https://blogs.msdn.microsoft.com/ieinternals/2009/09/18/understanding-domain-names-in-internet-explorer/