I can’t find a valid way to restrict this permission. I would ideally like to restrict the permission to work in a particular VPC and/or subnet. I’m unsure where in the documentation to look & have tried numerous approaches with all failing.

My JSON is like this roughly & have tried lots of things in the resource and condition fields:

{
            "Effect": "Allow",
            "Action": [
                "ec2:CreateNetworkInterface",
                "ec2:DeleteNetworkInterface"
            ],
            "Resource": [
                "*"
            ],
            "Condition": {
                "StringLike": {
                    "ec2:XXXXX": "*"
                }
            }
        }