cis-aws-euc-5-6

name	cis-aws-euc-5.6
description	Ensure internet access is granted and managed through your VPC
category	cis-end-user-compute
version	1.2.0
author	cyberstrike-official
tags	["cis","aws","end-user-compute","appstream","network-security","vpc"]
cis_id	5.6
cis_benchmark	CIS AWS End User Compute Services Benchmark v1.2.0
tech_stack	["aws"]
cwe_ids	["CWE-668"]
chains_with	["cis-aws-euc-5.1"]
prerequisites	["cis-aws-euc-5.1"]
severity_boost	{}

Ensure internet access is granted and managed through your VPC (Automated)

Profile Applicability

• Level 1

Description

Default Internet Access from your fleet streaming instances should remain unchecked.

Rationale

When Default Internet Access is enabled, AppStream 2.0 uses the internet gateway in the VPC public subnet to connect to the public internet. The streaming instances are then assigned public IP addresses that are directly accessible from the internet.

Internet Access from fleet streaming instances should be controlled using a NAT gateway in the VPC. When Default Internet Access is not enabled, streaming instances are assigned a private IP address that are not directly accessible from the internet.

Impact

None - this is a security best practice.

Audit Procedure

Perform the following steps to view the Fleet settings in AppStream.

Using AWS Console

1. Log in to the AppStream 2.0 console at https://console.aws.amazon.com/appstream2
2. In the left pane click on Fleets
3. Select the link for the fleet name you wish to view
4. On the Network details section confirm that Default Internet Access is set to Disabled

If Default internet access is not set to disabled refer to the remediation below.

Using AWS CLI

Not applicable - must be audited via Console.

Expected Result

Default Internet Access is disabled for the fleet.

Remediation

Using AWS Console

Perform the following steps to view the Fleet settings in AppStream:

1. Log in to the AppStream 2.0 console at https://console.aws.amazon.com/appstream2
2. In the left pane click on Fleets
3. Select the link for the fleet name you wish to edit
4. Click Actions, Stop
5. Scroll to the Network details section and click Edit
6. Deselect Default Internet Access
7. Click Save changes

Using AWS CLI

Not applicable - must be configured via Console.

Default Value

By default, internet access is not enabled; the box is "unchecked" in the management console.

References

1. https://docs.aws.amazon.com/appstream2/latest/developerguide/set-up-stacks-fleets.html