Microsoft 365
TMA-M365-5.2.3.7
Ensure the email OTP authentication method is disabled
Description
Authentication methods support a wide variety of scenarios for signing in to Microsoft 365 resources. Some of these methods are inherently more secure than others but require more investment in time to get users enrolled and operational. The email one-time passcode feature is a way to authenticate B2B collaboration users when they can't be authenticated through other means, such as Microsoft Entra ID, Microsoft account (MSA), or social identity providers. When a B2B guest user tries to redeem your invitation or sign in to your shared resources, they can request a temporary passcode, which is sent to their email address. Then they enter this passcode to continue signing in. The recommended state is to Disable email OTP. Traditional MFA methods such as SMS codes, email-based OTPs, and push notifications are becoming less effective against today’s attackers. Sophisticated phishing campai...
Méthode de vérification
Méthode d'audit: Revue manuelle
To audit using the UI: 1. Navigate to Microsoft Entra admin center https://entra.microsoft.com/. 2. Expand Entra ID > Authentication methods and select Policies. 3. Verify that Email OTP is set to No in the Enabled column. To audit using Powershell: 1. Connect to Graph using Connect-MgGraph -Scopes "Policy.Read.All" 2. Run the following: (Get-MgPolicyAuthenticationMethodPolicy).AuthenticationMethodConfigurations 3. Verify the id type Email is set to disabled.
Méthode de correction
Méthode de correction: Recommandation ou correctif d'infrastructure
To remediate using the UI: 1. Navigate to Microsoft Entra admin center https://entra.microsoft.com/. 2. Expand Entra ID > Authentication methods and select Policies. 3. Click on Email OTP. 4. Change the Enable toggle to the off position\ 5. Click Save. Note: If the save button remains greyed out after toggling a method off, then first turn it back on and then change the position of the Target selection (all users or select groups). Turn the method off again and save. This was observed to be a bug in the UI at the time this document was published. To remediate using Powershell: 1. Connect to Graph using Connect-MgGraph -Scopes "Policy.ReadWrite.AuthenticationMethod" 2. Run the following: $params = @( @{ Id = "Email"; State = "disabled" } ) Update-MgPolicyAuthenticationMethodPolicy -AuthenticationMethodConfigurations $params
Propriétés
- Systèmes d'exploitation
- Tous
- Étiquettes
- authm365saas
- Référence
- CIS Microsoft 365 Foundations Benchmark v7.0.0 - 5.2.3.7 Ensure the email OTP authentication method is disabled