Skip to content
Vol. 1 · Ed. 2026
CyberGlossary
Entry № 753

Microsoft Entra ID

Microsoft Entra ID とは何ですか?

Microsoft Entra IDMicrosoft's cloud identity service — formerly Azure Active Directory — providing identity, single sign-on, MFA, Conditional Access, and external-identity capabilities for Microsoft 365 and millions of integrated SaaS applications.


Microsoft Entra ID is the rebrand of Azure Active Directory, announced in July 2023 and rolled out through 2023–2024. As a product it is essentially unchanged: the same cloud identity, authentication, and authorization service backing Microsoft 365, Azure, and millions of integrated SaaS applications. The Entra brand also covers a broader family — Entra ID Governance (formerly Azure AD Identity Governance), Entra Verified ID (decentralized identifiers), Entra Permissions Management (CIEM), Entra Internet Access and Entra Private Access (SSE/ZTNA). The naming change is operationally important because it appears throughout documentation, MSGraph endpoints (still `graph.microsoft.com`), Conditional Access UIs, audit logs, and security tooling — meaning anyone writing detections, runbooks, or training has had to migrate terminology. From a security perspective Entra ID is the de facto IdP for most enterprises, and its primary attack surfaces are well known: consent phishing, device-code phishing, OAuth-token theft, Pass-the-PRT, Golden SAML against AD FS, and Storm-0558-style key compromise. Conditional Access, FIDO2-only sign-in policies, and Identity Protection are the corresponding defensive controls.

  1. 01

    A Conditional Access policy blocks legacy authentication protocols and requires FIDO2-bound sign-in for all global administrators.

  2. 02

    A SIEM detection updates its data source from 'AzureActiveDirectory' to 'Microsoft Entra ID' but continues to reference the same Graph endpoints and event schema.

よくある質問

Microsoft Entra ID とは何ですか?

Microsoft's cloud identity service — formerly Azure Active Directory — providing identity, single sign-on, MFA, Conditional Access, and external-identity capabilities for Microsoft 365 and millions of integrated SaaS applications. サイバーセキュリティの ID とアクセス カテゴリに属します。

Microsoft Entra ID とはどういう意味ですか?

Microsoft's cloud identity service — formerly Azure Active Directory — providing identity, single sign-on, MFA, Conditional Access, and external-identity capabilities for Microsoft 365 and millions of integrated SaaS applications.

Microsoft Entra ID はどのように機能しますか?

Microsoft Entra ID is the rebrand of Azure Active Directory, announced in July 2023 and rolled out through 2023–2024. As a product it is essentially unchanged: the same cloud identity, authentication, and authorization service backing Microsoft 365, Azure, and millions of integrated SaaS applications. The Entra brand also covers a broader family — Entra ID Governance (formerly Azure AD Identity Governance), Entra Verified ID (decentralized identifiers), Entra Permissions Management (CIEM), Entra Internet Access and Entra Private Access (SSE/ZTNA). The naming change is operationally important because it appears throughout documentation, MSGraph endpoints (still `graph.microsoft.com`), Conditional Access UIs, audit logs, and security tooling — meaning anyone writing detections, runbooks, or training has had to migrate terminology. From a security perspective Entra ID is the de facto IdP for most enterprises, and its primary attack surfaces are well known: consent phishing, device-code phishing, OAuth-token theft, Pass-the-PRT, Golden SAML against AD FS, and Storm-0558-style key compromise. Conditional Access, FIDO2-only sign-in policies, and Identity Protection are the corresponding defensive controls.

Microsoft Entra ID からどのように防御しますか?

Microsoft Entra ID に対する防御は通常、上記の定義で述べたとおり、技術的統制と運用上の実践を組み合わせます。

Microsoft Entra ID の別名は何ですか?

一般的な別名: Azure AD, Azure Active Directory, AAD。

関連用語