Ensure there is an Amazon CloudWatch alarm set up in your AWS account that is triggered each time a VPC Internet Gateway or a VPC VPN Customer Gateway configuration change is made. This CloudWatch alarm must fire every time an AWS API call is performed to create, update or delete a VPC Customer/Internet Gateway.
This rule can help you with the following compliance standards:
- CISAWSF
- PCI
- APRA
- MAS
- NIST4
For further details on compliance standards supported by Conformity, see here.
This rule can help you work with the AWS Well-Architected Framework.
This rule resolution is part of the Conformity Security & Compliance tool for AWS.
Using Amazon CloudWatch alarms to detect configuration changes involving your AWS VPC Customer/Internet Gateway(s) will help you prevent any unexpected modifications that may lead to unrestricted network access, loss of connection between your AWS VPC and Internet or loss of VPN connection between your VPC and the on-premise datacenter(s) linked.
Note 1: For this rule Cloud Conformity assumes that the CloudTrail service is already enabled to stream event log data to CloudWatch within your AWS account, otherwise see this rule to enable AWS Cloudtrail – CloudWatch integration.
Note 2: You have also the option to implement this conformity rule with AWS CloudFormation. Download the required CloudFormation template from this URL and follow the AWS instructions available here.
Audit
To determine if there are any CloudWatch alarms set up to monitor AWS VPCs configuration changes within your AWS account, perform the following:
Remediation / Resolution
Step 1: Create a Simple Notification Service (SNS) topic and the necessary subscription to send email notifications whenever the appropriate Amazon CloudWatch alarm (created at Step 2) is triggered.
Remediation / Resolution
Step 2: Create the necessary metric filter and the CloudWatch alarm that will fire and send notifications whenever an AWS VPC Customer/Internet Gateway configuration will change.
References
- AWS Documentation
- Amazon CloudWatch Concepts
- Your Customer Gateway
- Internet Gateways
- Creating CloudWatch Alarms for CloudTrail Events
- Create a Topic
- Subscribe to a Topic
- Using an AWS CloudFormation Template to Create CloudWatch Alarms
- AWS Command Line Interface (CLI) Documentation
- cloudwatch
- describe-alarms-for-metric
- put-metric-alarm
- put-metric-filter
- sns
- create-topic
- subscribe
- confirm-subscription