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Metadata at May 7, 2026

Message ID

MC1303719

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Published

May 7, 2026

Service

Microsoft Entra

Tag

Admin impact

Act by

Aug 11, 2026

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MC1303719 - Microsoft Entra: Upcoming changes to federatedTokenValidationPolicy default settings

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What changed since this version

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Updated August 18, 2026: We have updated the timeline. Thank you for your patience. 

Introduction

To strengthen security for federated authentication, Microsoft Entra will update the default behavior of federatedTokenValidationPolicy. This policy governs how Microsoft Entra validates federated authentication tokens and determines whether sign-ins are allowed when the internalDomainFederation does not match the user’s UPN domain. Previously, enforcing this behavior required explicit tenant configuration, but it will now be applied by default to reduce the risk of unintended cross-domain sign-ins caused by misconfigured or overly permissive federation trust relationships.

When this will happen

General Availability (Worldwide, GCC, GCCH, and DoD): We will begin rolling out in mid-August 2026 and expect to complete by mid-end of August 2026 (previously mid-August).

How this affects your organization

Who is affected

  • Microsoft 365 tenants using federated authentication in Microsoft Entra
  • Admins managing federated domains that were configured before December 2025
  • Applies only to federated domains that have an internalDomainFederation object

What will happen

  • By default, federated sign-ins will be blocked when the internalDomainFederation does not match the user’s UPN domain.
  • The internalDomainFederation object is typically created automatically during federation setup with Active Directory Federation Services (AD FS) or other identity providers (IdPs).
  • This stricter default behavior of the federatedTokenValidationPolicy is already enforced for federated domains added since December 2025.
  • After this change, the same behavior will apply to all existing federated domains with an internalDomainFederation object.
  • Impacted sign-ins will fail with the error:

AADSTS5000820: Sign-in blocked by Federated Token Validation policy. Contact your administrator for details.

  • There is no change to the user experience unless cross-domain federated sign-ins are currently occurring.

What you can do to prepare

  • No action is required for most organizations.
  • Cross-domain federated sign-ins will be blocked automatically as part of this security improvement.
  • Organizations that rely on cross-domain federated sign-ins should review their existing federation configurations before rollout.
  • (Strongly discouraged) If required for business continuity, Security Administrators, Hybrid Identity Administrators, or External Identity Provider Administrators can use Microsoft Graph to create a custom federatedTokenValidationPolicy with rootDomains = none to allow cross-domain sign-ins.
  • Communicate this change to identity and helpdesk teams to reduce support escalations.

Learn more:

Compliance considerations

QuestionAnswer
Does the change include an admin control, and can it be controlled through Microsoft Entra ID group membership?Yes. Administrators can configure a custom federatedTokenValidationPolicy using Microsoft Graph to override the default behavior, although this is strongly discouraged due to security risks.
Does the change modify, interrupt, or disable Purview capabilities such as Data Loss Prevention, Information Protection, Conditional Access, audit logging, eDiscovery, encryption, or retention policies?Yes. This change affects authentication enforcement behavior in Microsoft Entra, which may indirectly influence how Conditional Access policies evaluate federated sign-ins.

Snapshot from May 7, 2026

Introduction

To strengthen security for federated authentication, Microsoft Entra will update the default behavior of federatedTokenValidationPolicy. This policy governs how Microsoft Entra validates federated authentication tokens and determines whether sign-ins are allowed when the internalDomainFederation does not match the user’s UPN domain. Previously, enforcing this behavior required explicit tenant configuration, but it will now be applied by default to reduce the risk of unintended cross-domain sign-ins caused by misconfigured or overly permissive federation trust relationships.

When this will happen

General Availability (Worldwide, GCC, GCCH, and DoD): We will begin rolling out in mid-August 2026 and expect to complete by mid-August 2026.

How this affects your organization

Who is affected

  • Microsoft 365 tenants using federated authentication in Microsoft Entra
  • Admins managing federated domains that were configured before December 2025
  • Applies only to federated domains that have an internalDomainFederation object

What will happen

  • By default, federated sign-ins will be blocked when the internalDomainFederation does not match the user’s UPN domain.
  • The internalDomainFederation object is typically created automatically during federation setup with Active Directory Federation Services (AD FS) or other identity providers (IdPs).
  • This stricter default behavior of the federatedTokenValidationPolicy is already enforced for federated domains added since December 2025.
  • After this change, the same behavior will apply to all existing federated domains with an internalDomainFederation object.
  • Impacted sign-ins will fail with the error:

AADSTS5000820: Sign-in blocked by Federated Token Validation policy. Contact your administrator for details.

  • There is no change to the user experience unless cross-domain federated sign-ins are currently occurring.

What you can do to prepare

  • No action is required for most organizations.
  • Cross-domain federated sign-ins will be blocked automatically as part of this security improvement.
  • Organizations that rely on cross-domain federated sign-ins should review their existing federation configurations before rollout.
  • (Strongly discouraged) If required for business continuity, Security Administrators, Hybrid Identity Administrators, or External Identity Provider Administrators can use Microsoft Graph to create a custom federatedTokenValidationPolicy with rootDomains = none to allow cross-domain sign-ins.
  • Communicate this change to identity and helpdesk teams to reduce support escalations.

Learn more:

Compliance considerations

QuestionAnswer
Does the change include an admin control, and can it be controlled through Microsoft Entra ID group membership?Yes. Administrators can configure a custom federatedTokenValidationPolicy using Microsoft Graph to override the default behavior, although this is strongly discouraged due to security risks.
Does the change modify, interrupt, or disable Purview capabilities such as Data Loss Prevention, Information Protection, Conditional Access, audit logging, eDiscovery, encryption, or retention policies?Yes. This change affects authentication enforcement behavior in Microsoft Entra, which may indirectly influence how Conditional Access policies evaluate federated sign-ins.