2.6 Ensure hardware MFA is enabled for the 'root' user account

Information

The 'root' user account is the most privileged user in an AWS account. MFA adds an extra layer of protection on top of a username and password. With MFA enabled, when a user signs in to an AWS website, they are prompted for their username and password as well as an authentication code from their MFA device. For Level 2, it is recommended that the 'root' user account be protected with a hardware MFA device.

Where an AWS Organization is using centralized root access, root credentials can be removed from member accounts. In that case, it is neither possible nor necessary to configure root MFA in the member account.

A hardware MFA device has a smaller attack surface than a virtual MFA. For example, a hardware MFA device does not inherit the risks associated with mobile devices on which virtual MFA applications reside.

Note: Using hardware MFA for numerous AWS accounts may create logistical device management challenges. In such cases, consider applying this Level 2 recommendation selectively to the highest-security AWS accounts, while applying the Level 1 recommendation to others.

NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.

Solution

Perform the following to configure hardware MFA for the 'root' user account:

From Console:

- Sign in to the AWS Management Console using the root account
- Click on <root_account> at the top right and select Security Credentials from the drop-down list
- Under Multi-Factor Authentication (MFA), locate the root user
- If a virtual MFA device is already assigned, remove it before proceeding
- Click Assign MFA device (or Manage MFA, depending on UI version)
- Select Security key or hardware MFA device
- Enter the required device details (e.g., serial number or follow prompts for security key)
- Enter authentication codes if required
- Click Assign MFA

Impact:

Without hardware MFA, root account protection may be more susceptible to compromise compared to hardware-based authentication, increasing the risk of unauthorized access.

See Also

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

Item Details

Category: IDENTIFICATION AND AUTHENTICATION

References: 800-53|IA-2(1), CCE|CCE-78911-5, CSCv7|4.5

Plugin: amazon_aws

Control ID: cb970de0c8fca83e98ddeda56c978c19e3c2b17cd3226f1200b3dfae902c93d0