2.18 Ensure that IAM External Access Analyzer is enabled for all regions

Information

Enable IAM External Access Analyzer for all resources in each active AWS region.

IAM Access Analyzer is a service that analyzes resource policies to identify resources that can be accessed from outside the account. After the analyzer is enabled, scan results are displayed in the console showing accessible resources. These results help determine whether unintended access is permitted, making it easier for administrators to monitor least privilege access. Access Analyzer analyzes only policies applied to resources within the same AWS region.

IAM External Access Analyzer helps identify resources in your account or organization that are shared with external entities. This allows detection of unintended access to resources and data. It continuously monitors policies for services such as S3 buckets, IAM roles, KMS keys, Lambda functions, and SQS queues.

Solution

From Console:

Perform the following to enable IAM Access Analyzer for IAM policies:

- Open the IAM console at https://console.aws.amazon.com/iam/
- Choose Access analyzer
- Select Create analyzer
- Select External access analyzer
- Confirm the region
- Optionally provide a name and tags
- Select Create analyzer
- Repeat for each active region

From Command Line:

- Create an analyzer in a region:

aws accessanalyzer list-analyzers --type <ACCOUNT|ORGANIZATION> --region <region_name> | grep status
- Repeat for each region as required

Impact:

If IAM External Access Analyzer is not enabled, unintended external access to resources may go undetected, increasing the risk of data exposure or unauthorized access.

See Also

https://workbench.cisecurity.org/benchmarks/24575

Item Details

Category: ACCESS CONTROL, MEDIA PROTECTION

References: 800-53|AC-3, 800-53|AC-5, 800-53|AC-6, 800-53|MP-2, CSCv7|14.6

Plugin: amazon_aws

Control ID: 9a7fa759e0a0c9ee1b25168ee8e0287f93b3d73a95baa16d878a550048b77441