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Revoke user access in Microsoft Entra ID

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Scenarios that could require an administrator to revoke all access for a user include compromised accounts, employee termination, and other insider threats. Depending on the complexity of the environment, administrators can take several steps to ensure access is revoked. In some scenarios, there could be a period between the initiation of access revocation and when access is effectively revoked.

To mitigate the risks, you must understand how tokens work. There are many kinds of tokens, which fall into one of the patterns mentioned in the sections below.

Access tokens and refresh tokens

Access tokens and refresh tokens are frequently used with thick client applications, and also used in browser-based applications such as single page apps.

  • When users authenticate to Microsoft Entra ID, part of Microsoft Entra, authorization policies are evaluated to determine if the user can be granted access to a specific resource.

  • If authorized, Microsoft Entra ID issues an access token and a refresh token for the resource.

  • Access tokens issued by Microsoft Entra ID by default last for 1 hour. If the authentication protocol allows, the app can silently reauthenticate the user by passing the refresh token to the Microsoft Entra ID when the access token expires.

Microsoft Entra ID then reevaluates its authorization policies. If the user is still authorized, Microsoft Entra ID issues a new access token and refreshes token.

Access tokens can be a security concern if access must be revoked within a time that is shorter than the lifetime of the token, which is usually around an hour. For this reason, Microsoft is actively working to bring continuous access evaluation to Office 365 applications, which helps ensure invalidation of access tokens in near real time.

Session tokens (cookies)

Most browser-based applications use session tokens instead of access and refresh tokens.

  • When a user opens a browser and authenticates to an application via Microsoft Entra ID, the user receives two session tokens. One from Microsoft Entra ID and another from the application.

  • Once an application issues its own session token, access to the application is governed by the application's session. At this point, the user is affected by only the authorization policies that the application is aware of.

  • The authorization policies of Microsoft Entra ID are reevaluated as often as the application sends the user back to Microsoft Entra ID. Reevaluation usually happens silently, though the frequency depends on how the application is configured. It's possible that the app may never send the user back to Microsoft Entra ID as long as the session token is valid.

  • For a session token to be revoked, the application must revoke access based on its own authorization policies. Microsoft Entra ID can't directly revoke a session token issued by an application.

Revoke access for a user in the hybrid environment

For a hybrid environment with on-premises Active Directory synchronized with Microsoft Entra ID, Microsoft recommends IT admins to take the following actions. If you have a Microsoft Entra-only environment, skip to the Microsoft Entra environment section.

On-premises Active Directory environment

As an admin in the Active Directory, connect to your on-premises network, open PowerShell, and take the following actions:

  1. Disable the user in Active Directory. Refer to Disable-ADAccount.

    Disable-ADAccount -Identity johndoe

  2. Reset the user's password twice in the Active Directory. Refer to Set-ADAccountPassword.

    Note

    The reason for changing a user's password twice is to mitigate the risk of pass-the-hash, especially if there are delays in on-premises password replication. If you can safely assume this account isn't compromised, you may reset the password only once.

    Important

    Don't use the example passwords in the following cmdlets. Be sure to change the passwords to a random string.

    Set-ADAccountPassword -Identity johndoe -Reset -NewPassword (ConvertTo-SecureString -AsPlainText "p@ssw0rd1" -Force)
Set-ADAccountPassword -Identity johndoe -Reset -NewPassword (ConvertTo-SecureString -AsPlainText "p@ssw0rd2" -Force)

Microsoft Entra environment

As an administrator in Microsoft Entra ID, open PowerShell, run Connect-MgGraph, and take the following actions:

  1. Disable the user in Microsoft Entra ID. Refer to Update-MgUser.

    $User = Get-MgUser -Search UserPrincipalName:'johndoe@contoso.com' -ConsistencyLevel eventual
Update-MgUser -UserId $User.Id -AccountEnabled:$false

  2. Revoke the user's Microsoft Entra ID refresh tokens. Refer to Revoke-MgUserSignInSession.

    Revoke-MgUserSignInSession -UserId $User.Id

  3. Disable the user's devices. Refer to Get-MgUserRegisteredDevice.

    $Device = Get-MgUserRegisteredDevice -UserId $User.Id 
Update-MgDevice -DeviceId $Device.Id -AccountEnabled:$false

Note

For information on specific roles that can perform these steps review Microsoft Entra built-in roles

Note

Azure AD and MSOnline PowerShell modules are deprecated as of March 30, 2024. To learn more, read the deprecation update. After this date, support for these modules are limited to migration assistance to Microsoft Graph PowerShell SDK and security fixes. The deprecated modules will continue to function through March, 30 2025.

We recommend migrating to Microsoft Graph PowerShell to interact with Microsoft Entra ID (formerly Azure AD). For common migration questions, refer to the Migration FAQ. Note: Versions 1.0.x of MSOnline may experience disruption after June 30, 2024.

When access is revoked

Once admins have taken the above steps, the user can't gain new tokens for any application tied to Microsoft Entra ID. The elapsed time between revocation and the user losing their access depends on how the application is granting access:

  • For applications using access tokens, the user loses access when the access token expires.

  • For applications that use session tokens, the existing sessions end as soon as the token expires. If the disabled state of the user is synchronized to the application, the application can automatically revoke the user's existing sessions if it's configured to do so. The time it takes depends on the frequency of synchronization between the application and Microsoft Entra ID.

Best practices

  • Deploy an automated provisioning and deprovisioning solution. Deprovisioning users from applications is an effective way of revoking access, especially for applications that use sessions tokens or allow users to sign in directly without a Microsoft Entra or Windows Server AD token. Develop a process to also deprovision users to apps that don't support automatic provisioning and deprovisioning. Ensure applications revoke their own session tokens and stop accepting Microsoft Entra access tokens even if they're still valid.

  • Manage your devices and applications with Microsoft Intune. Intune-managed devices can be reset to factory settings. If the device is unmanaged, you can wipe the corporate data from managed apps. These processes are effective for removing potentially sensitive data from end users' devices. However, for either process to be triggered, the device must be connected to the internet. If the device is offline, the device will still have access to any locally stored data.

Note

Data on the device cannot be recovered after a wipe.

Next steps