prowler/docs/tutorials/allowlist.md

Allowlisting

Sometimes you may find resources that are intentionally configured in a certain way that may be a bad practice but it is all right with it, for example an AWS S3 Bucket open to the internet hosting a web site, or an AWS Security Group with an open port needed in your use case.

Allowlist option works along with other options and adds a WARNING instead of INFO, PASS or FAIL to any output format.

You can use -w/--allowlist-file with the path of your allowlist yaml file, but first, let's review the syntax.

## Allowlist Yaml File Syntax

### Account, Check and/or Region can be * to apply for all the cases
### Resources is a list that can have either Regex or Keywords:
###########################  ALLOWLIST EXAMPLE  ###########################
Allowlist:
Accounts:
    "123456789012":
    Checks:
        "iam_user_hardware_mfa_enabled":
        Regions:
            - "us-east-1"
        Resources:
            - "user-1"           # Will ignore user-1 in check iam_user_hardware_mfa_enabled
            - "user-2"           # Will ignore user-2 in check iam_user_hardware_mfa_enabled
        "*":
        Regions:
            - "*"
        Resources:
            - "test"             # Will ignore every resource containing the string "test" in every account and region

    "*":
    Checks:
        "s3_bucket_object_versioning":
        Regions:
            - "eu-west-1"
            - "us-east-1"
        Resources:
            - "ci-logs"           # Will ignore bucket "ci-logs" AND ALSO bucket "ci-logs-replica" in specified check and regions
            - "logs"              # Will ignore EVERY BUCKET containing the string "logs" in specified check and regions
            - "[[:alnum:]]+-logs" # Will ignore all buckets containing the terms ci-logs, qa-logs, etc. in specified check and regions

Supported Allowlist Locations

The allowlisting flag supports the following locations:

### Local file You will need to pass the local path where your Allowlist YAML file is located:

prowler <provider> -w allowlist.yaml

AWS S3 URI

You will need to pass the S3 URI where your Allowlist YAML file was uploaded to your bucket:

prowler aws -w s3://<bucket>/<prefix>/allowlist.yaml

Make sure that the used AWS credentials have s3:GetObject permissions in the S3 path where the allowlist file is located.

AWS DynamoDB Table ARN

You will need to pass the DynamoDB Allowlist Table ARN:

prowler aws -w arn:aws:dynamodb:<region_name>:<account_id>:table/<table_name>

1. The DynamoDB Table must have the following String keys:

• The Allowlist Table must have the following columns:
  • Accounts (String): This field can contain either an Account ID or an * (which applies to all the accounts that use this table as an allowlist).
  • Checks (String): This field can contain either a Prowler Check Name or an * (which applies to all the scanned checks).
  • Regions (List): This field contains a list of regions where this allowlist rule is applied (it can also contains an * to apply all scanned regions).
  • Resources (List): This field contains a list of regex expressions that applies to the resources that are wanted to be allowlisted.

Make sure that the used AWS credentials have dynamodb:PartiQLSelect permissions in the table.