| name | cis-aws-foundations-5.12 |
| description | Ensure changes to network gateways are monitored |
| category | cis-monitoring |
| version | 7.0.0 |
| author | cyberstrike-official |
| tags | ["cis","aws","monitoring","cloudwatch","cloudtrail","metric-filters","alarms","network-gateway","internet-gateway","vpc"] |
| cis_id | 5.12 |
| cis_benchmark | CIS AWS Foundations Benchmark v7.0.0 |
| tech_stack | ["aws"] |
| cwe_ids | [] |
| chains_with | ["cis-aws-foundations-4.1","cis-aws-foundations-4.2"] |
| prerequisites | [] |
| severity_boost | {} |
Ensure changes to network gateways are monitored
Description
Real-time monitoring of API calls can be achieved by directing CloudTrail Logs to CloudWatch Logs or an external Security Information and Event Management (SIEM) environment, and establishing corresponding metric filters and alarms.
Network gateways are required to send and receive traffic to a destination outside of a VPC. It is recommended that a metric filter and alarm be established for changes to network gateways.
Rationale
CloudWatch is an AWS native service that allows you to observe and monitor resources and applications. CloudTrail logs can also be sent to an external Security Information and Event Management (SIEM) environment for monitoring and alerting.
Monitoring changes to network gateways will help ensure that all ingress/egress traffic traverses the VPC border via a controlled path.
Impact
Monitoring changes to network gateways helps detect unauthorized modifications that could compromise network security. Implementing automated monitoring and alerts can improve incident response times, but it may require additional configuration and maintenance efforts.
Audit Procedure
Using AWS CLI
If you are using CloudTrail trails and CloudWatch, perform the following to ensure that there is at least one active multi-region CloudTrail trail with the prescribed metric filters and alarms configured:
- Identify the log group name that is configured for use with the active multi-region CloudTrail trail:
- List all CloudTrail trails:
aws cloudtrail describe-trails
-
Identify multi-region CloudTrail trails: Trails with "IsMultiRegionTrail" set to true
-
Note the value associated with "Name":<trail-name>
-
Note the <trail-log-group-name> within the value associated with "CloudWatchLogsLogGroupArn"
- Example:
arn:aws:logs:<region>:<account-id>:log-group:<trail-log-group-name>:*
-
Ensure the identified multi-region CloudTrail trail is active:
aws cloudtrail get-trail-status --name <trail-name>
aws cloudtrail get-event-selectors --trail-name <trail-name>