Restrict s3 bucket Access to VPC

Allow access to s3 bucket only from vpc

Currently I am evaluating options to lockdown permissions to my S3 Buckets as part of Security Enhancements. These are the steps I followed to lock down S3 Bucket access only to my VPC

Create VPC End Points

VPC End Points Screen Shot

Attach the S3 Bucket Policy to Restrict Access

{
	"Version": "2012-10-17",
	"Id": "Policy123456789",
	"Statement": [
		{
			"Sid": "Stmt123456789",
			"Effect": "Deny",
			"Principal": "*",
			"Action": "s3:*",
			"Resource": "arn:aws:s3:::example-confidential/*",
			"Condition": {
				"StringNotEquals": {
					"aws:sourceVpc": "vpc-2f2b202b"
				}
			}
		}
	]
}

Access the Buckets Outside VPC

Once you have attached the policy, if you access the S3 Files through console not being on VPC, you will receive the error.

AccessDenied Access Denied 14FB0BEFD8A0C8E5 JrFOr/6Fe20lyMxjCy6lPhJIJ8sj3kG7zSiel2kcvv6OUssHQ2W/e7bYTjD3hXjX2m1/aHB+G1I=

Access the Buckets from VPC

If you log into a EC2 Instance which is hosted on VPC, you will be able to access the s3 Bucket.

SSH Into your EC2 Machine and verify your VPC through Instance Meta Data Store.

[ec2-user]# curl http: //169.254.169.254/latest/meta-data/network/interfaces/macs/
01:ed:88:51:f6:29/ [ec2-user]# curl http: //169.254.169.254/latest/meta-data/network//interfaces/macs/01:ed:88:51:f6:29/vpc-id
vpc-2f2b202b

If you execute s3 commands to access the bucket, you will be able to access the S3 Bucket without access denied error.

aws s3 ls example-confidential aws s3 cp s3:: //example-confidential/SampleConfidentialFile.txt  SampleConfidentialFile.txt