Connection not secured when pointing a subdomain to Cloudfront

Question

I have a domain name hosted on an external server and I'd like to point a subdomain to an S3 bucket using Cloudfront.

I'm already able to point my domain to my S3 bucket (subdomain.s3.amazonaws.com) but it's not HTTPS secured, this is why I created a SSL certificate on AWS, a CloudFront distribution linked to my S3 Bucket and I pointed my subdomain (assets.example.com) to my Cloudfront's domain (xxx.cloudfront.net).

But now, when I try to access my subdomain, I'm getting the following error:

How can I solve this issue? Is there something I misconfigured on my Cloudfront distribution?

Answer 1

You wouldn't have probably added assets.example.com to CloudFront's CNAME/Alternate domain name field.

CloudFront CNAME

Also, a certificate a required on CloudFront with the Subject assets.example.com.

Answer 2

https://aws.amazon.com/premiumsupport/knowledge-center/cloudfront-domain-https/ --> suggest you check each of those points (eg no full stops in your S3 bucket name)

Probably worth checking cipher comparability too: https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/secure-connections-supported-viewer-protocols-ciphers.html#secure-connections-supported-ciphers