Comment by simonw
Comment by simonw 5 days ago
S3: "Block Public Access is now enabled by default on new buckets."
On the one hand, this is obviously the right decision. The number of giant data breeches caused by incorrectly configured S3 buckets is enormous.
But... every year or so I find myself wanting to create an S3 bucket with public read access to I can serve files out of it. And every time I need to do that I find something has changed and my old recipe doesn't work any more and I have to figure it out again from scratch!
The thing to keep in mind with the "Block Public Access" setting is that is a redundancy built in to save people from making really big mistakes.
Even if you have a terrible and permissive bucket policy or ACLs (legacy but still around) configured for the S3 bucket, if you have Block Public Access turned on - it won't matter. It still won't allow public access to the objects within.
If you turn it off but you have a well scoped and ironclad bucket policy - you're still good! The bucket policy will dictate who, if anyone, has access. Of course, you have to make sure nobody inadvertantly modifies that bucket policy over time, or adds an IAM role with access, or modifies the trust policy for an existing IAM role that has access, and so on.