7.2.10 (L1) Ensure reauthentication with verification code is restricted

Information

This setting configures if guests who use a verification code to access the site or links are required to reauthenticate after a set number of days.

The recommended state is 15 or less.

By increasing the frequency of times guests need to reauthenticate this ensures guest user access to data is not prolonged beyond an acceptable amount of time.

Solution

To remediate using the UI:

- Navigate to SharePoint admin center

https://admin.microsoft.com/sharepoint

- Click to expand Policies > Sharing
- Scroll to and expand More external sharing settings
- Set People who use a verification code must reauthenticate after this many days to 15 or less.

To remediate using PowerShell:

- Connect to SharePoint Online service using Connect-SPOService
- Run the following cmdlet:

Set-SPOTenant -EmailAttestationRequired $true -EmailAttestationReAuthDays 15

Impact:

Guests who use Microsoft 365 in their organization can sign in using their work or school account to access the site or document. After the one-time passcode for verification has been entered for the first time, guests will authenticate with their work or school account and have a guest account created in the host's organization.

Note: If OneDrive and SharePoint integration with Entra ID B2B is enabled as per the CIS Benchmark the one-time-passcode experience will be replaced. Please visit

Secure external sharing in SharePoint - SharePoint in Microsoft 365 | Microsoft Learn

for more information.

See Also

https://workbench.cisecurity.org/benchmarks/17682

Item Details

Category: IDENTIFICATION AND AUTHENTICATION

References: 800-53|IA-11

Plugin: microsoft_azure

Control ID: 4fb7fc464da9cb464ac1ea92150b4fe4eedab3cfbca34e8659f79af5427e00db