Detections
Analytics

MS.AAD.1.1v1 - Legacy authentication SHALL be blocked.

Information

The security risk of allowing legacy authentication protocols is they do not support MFA. Blocking legacy protocols reduces the impact of user credential theft.

Solution

1. [Determine if an agency's existing applications use legacy authentication](https://learn.microsoft.com/en-us/entra/identity/conditional-access/block-legacy-authentication#identify-legacy-authentication-use) before blocking legacy authentication across the entire application base.

2. Create a Conditional Access policy to block legacy authentication

 Users > Include > All users

 Target resources > Include > All resources (formerly 'All cloud apps')

 Conditions > Client apps > Configure > Yes > Legacy authentication clients > Select only Exchange ActiveSync clients and Other clients

 Access controls > Grant > Block Access

See Also

https://github.com/cisagov/ScubaGear/tree/v1.8.0/

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-7

Plugin: microsoft_azure

Control ID: b38e467f0bdfc005d5439ea3450470bf468399f5f2f0f2ca630c1b1d682ebdd7