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How to Find AWS CloudTrail missing Alarm for VPC changes

Problem​

Monitoring unauthorized API calls will help reveal application errors and may reduce time to detect malicious activity.

info

This security check is part of the CIS Amazon Web Services Benchmarks and is rated severity medium.

Prerequisites​

This guide assumes that you have already installed and configured Resoto to collect your AWS cloud resources.

Directions​

  1. Execute the following search command in Resoto Shell or Resoto UI:

    > search is(aws_cloud_trail) and trail_is_multi_region_trail=true and trail_status.is_logging=true with(empty, --> is(aws_cloudwatch_log_group) with(any, --> is(aws_cloudwatch_metric_filter) and filter_pattern~"\s*\$\.eventName\s*=\s*CreateVpc.+\$\.eventName\s*=\s*DeleteVpc.+\$\.eventName\s*=\s*ModifyVpcAttribute.+\$\.eventName\s*=\s*AcceptVpcPeeringConnection.+\$\.eventName\s*=\s*CreateVpcPeeringConnection.+\$\.eventName\s*=\s*DeleteVpcPeeringConnection.+\$\.eventName\s*=\s*RejectVpcPeeringConnection.+\$\.eventName\s*=\s*AttachClassicLinkVpc.+\$\.eventName\s*=\s*DetachClassicLinkVpc.+\$\.eventName\s*=\s*DisableVpcClassicLink.+\$\.eventName\s*=\s*EnableVpcClassicLink"))
    ​kind=aws_cloud_trail, ..., region=resoto-poweruser
    ​kind=aws_cloud_trail, ..., account=poweruser-team

  2. Pipe the search command into the dump command:

    > search is(aws_cloud_trail) and trail_is_multi_region_trail=true and trail_status.is_logging=true with(empty, --> is(aws_cloudwatch_log_group) with(any, --> is(aws_cloudwatch_metric_filter) and filter_pattern~"\s*\$\.eventName\s*=\s*CreateVpc.+\$\.eventName\s*=\s*DeleteVpc.+\$\.eventName\s*=\s*ModifyVpcAttribute.+\$\.eventName\s*=\s*AcceptVpcPeeringConnection.+\$\.eventName\s*=\s*CreateVpcPeeringConnection.+\$\.eventName\s*=\s*DeleteVpcPeeringConnection.+\$\.eventName\s*=\s*RejectVpcPeeringConnection.+\$\.eventName\s*=\s*AttachClassicLinkVpc.+\$\.eventName\s*=\s*DetachClassicLinkVpc.+\$\.eventName\s*=\s*DisableVpcClassicLink.+\$\.eventName\s*=\s*EnableVpcClassicLink")) | dump
    ​reported:
    ​  id: /aws/cloudtrail/123
    ​  name: some-name
    ​  ctime: '2022-12-05T22:53:14Z'
    ​  kind: aws_cloud_trail
    ​  age: 2mo28d

    The command output will list the details of all non-compliant aws_cloud_trail resources.

  3. Fix detected issues by following the remediation steps:

    It is recommended that a metric filter and alarm be established for VPC Changes.

    note

    Please refer to the AWS CloudTrail documentation for details.

Further Reading​