---
title: 'AWS Assume Role in Prowler (CLI)'
---

## Authentication Overview

Prowler leverages the AWS SDK (Boto3) for authentication, following standard AWS authentication methods.

### Running Prowler Against Multiple Accounts

To execute Prowler across multiple AWS accounts using IAM Assume Role, choose one of the following approaches:

1. Custom Profile Configuration

    Set up a custom profile inside `~/.aws/config` with the necessary role information.

    Then call the profile using `prowler aws -p/--profile your-custom-profile`.

    - Role-Chaining Example Profile The `credential_source` parameter can be set to `Environment`, `Ec2InstanceMetadata`, or `EcsContainer`.

    - Using an Alternative Named Profile

        Instead of the `credential_source` parameter, `source_profile` can be used to specify a separate named profile.

        This profile must contain IAM user credentials with permissions to assume the target role. For additional details, refer to the AWS Assume Role documentation: [here](https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-role.html).

        ```
        [profile crossaccountrole]
        role_arn = arn:aws:iam::234567890123:role/SomeRole
        credential_source = EcsContainer
        ```

2. Using IAM Role Assumption in Prowler

    To allow Prowler to retrieve temporary credentials by using `Boto3` and run assessments on the specified account, use the `-R`/`--role <role_arn>` flag.

    ```sh
    prowler aws -R arn:aws:iam::<account_id>:role/<role_name>
    ```

    **Defining Session Duration and External ID**

    Optionally, specify the session duration (in seconds, default: 3600) and the external ID for role assumption:

    ```sh
    prowler aws -T/--session-duration <seconds> -I/--external-id <external_id> -R arn:aws:iam::<account_id>:role/<role_name>
    ```

## Custom Role Session Name in Prowler

### Setting a Custom Session Name

Prowler allows you to specify a custom Role Session name using the following flag:

```console
prowler aws --role-session-name <role_session_name>
```

<Note>
If not specified, it defaults to `ProwlerAssessmentSession`.

</Note>
## Role MFA Authentication

If your IAM Role is configured with Multi-Factor Authentication (MFA), use `--mfa` along with `-R`/`--role <role_arn>`. Prowler will prompt you to input the following values to obtain a temporary session for the IAM Role provided:

- ARN of your MFA device
- TOTP (Time-Based One-Time Password)

## Creating a Role for One or Multiple Accounts

To create an IAM role that can be assumed in one or multiple AWS accounts, use either a CloudFormation Stack or StackSet with the provided [template](https://github.com/prowler-cloud/prowler/blob/master/permissions/templates/cloudformation/prowler-scan-role.yml).

The template requires the following parameters:

- **ExternalId:** A unique identifier to prevent the [confused deputy problem](https://docs.aws.amazon.com/IAM/latest/UserGuide/confused-deputy.html)
- **AccountId:** *(Optional)* AWS Account ID that will assume the role (default: Prowler Cloud account)
- **IAMPrincipal:** *(Optional)* The IAM principal allowed to assume the role (default: `role/prowler*`)

<Warning>
From the CLI you assume the role with **your own** identity, not from Prowler Cloud. The `AccountId` and `IAMPrincipal` defaults target Prowler Cloud, so set **`AccountId`** to the account you run Prowler from and **`IAMPrincipal`** to your identity (for example `role/<name>` or `user/<name>`). Otherwise `sts:AssumeRole` fails with `AccessDenied`. See [Aligning the trust policy with your identity](/user-guide/providers/aws/authentication#trust-policy-align-iamprincipal-with-your-identity).
</Warning>

<Note>
To deploy the role across an entire AWS Organization from a single stack (Management Account role plus a service-managed StackSet for the member accounts), the template also accepts `DeployLocalRole`, `DeployStackSet`, `AWSOrganizationalUnitId`, `DeployFromDelegatedAdmin`, `EnableOrganizations`, `FailureTolerancePercentage`, and `RetainStacksOnAccountRemoval`. See [AWS Organizations in Prowler](/user-guide/providers/aws/organizations#native-cloudformation-stackset-deployment-recommended) for the full parameter reference.

</Note>

When running Prowler CLI, include the External ID using the `-I/--external-id` flag:

```sh
prowler aws -R arn:aws:iam::<account_id>:role/ProwlerScan -I <external_id>
```

<Note>
**Session Duration Considerations**: Depending on the number of checks performed and the size of your infrastructure, Prowler may require more than 1 hour to complete. Use the `-T <seconds>` option to allow up to 12 hours (43,200 seconds). If you need more than 1 hour, modify the _“Maximum CLI/API session duration”_ setting for the role. Learn more [here](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_use.html#id_roles_use_view-role-max-session).

⚠️ Important: If assuming roles via role chaining, there is a hard limit of 1 hour. Whenever possible, avoid role chaining to prevent session expiration issues. More details are available in footnote 1 below the table in the [AWS IAM guide](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_use.html).

</Note>