There’s no good defaults here. From AWS’s perspective the whole VM is in the same security context. It’s all untrusted customer code from the kernel on up. That’s the granularity on which policy can be applied. Either the whole VM can do something or it can’t. How you define your own security boundaries inside is your business. You can help AWS by doing your own access keys but most people would rather just also make their security boundary the VM and not have to think about it. Treat a compromised processes and a compromised host the same.
That's the "give up on container and process security" approach. It's a fine approach from any given user's standpoint. From an infra/tool provider standpoint, it ignores the intense demand that exists for establishing least privilege and defense-in-depth for containerized workloads. Fargate might be a good solution too.
This is backwards, you don't have to give up on container/process security just because AWS's own trust boundary is the VM. But to do that you can't assign VM-level privs. Something something eating cake.
Put yourself in AWS's position. Your customer is running a VM which you have only hypervisor level control over. Could be Linux, could be AIX, could be an appliance. How could you possibly implement user/process level security from the outside? How could you know what processes inside the opaque black box are the privileged ones?
Sorry, I don't think what you're saying makes sense. A key strength of AWS is that they don't use a "black box" approach when thinking about customer needs, and provide documentation and good defaults to help customers achieve their goals.
> From AWS’s perspective the whole VM is in the same security context.
That's AWS's perspective. But my perspective, as an AWS customer, is important as well. And I might want to run something on a VM that I myself don't necessarily trust - that is the ultimate benefit of an ephemeral, isolated VM.
Right, then you run that code in a VM that has no ambient privs. If you still need to do AWS access stuff then you just stick your access keys in files somewhere your untrusted process can't touch like if you weren't on AWS.
