-
Microsoft Entra ID Session Reuse with Suspicious Graph Access
May 10, 2025 · Domain: Cloud Data Source: Azure Data Source: Microsoft Entra ID Data Source: Microsoft Entra ID Sign-In Logs Data Source: Microsoft Graph Data Source: Microsoft Graph Activity Logs Use Case: Identity and Access Audit Use Case: Threat Detection Resources: Investigation Guide Tactic: Defense Evasion Tactic: Initial Access ·Identifies potential session hijacking or token replay in Microsoft Entra ID. This rule detects cases where a user signs in and subsequently accesses Microsoft Graph from a different IP address using the same session ID within a short time window. This may indicate the use of a stolen refresh/access token or session cookie to impersonate the user and interact with Microsoft services.
Read More -
This rule detects non-interactive authentication activity against SharePoint Online (
Office 365 SharePoint Online) by a user principal via theMicrosoft Authentication Brokerapplication. The session leverages a refresh token or Primary Refresh Token (PRT) without interactive sign-in, often used in OAuth phishing or token replay scenarios.
Read More -
Identifies when a new service principal is added in Microsoft Entra ID. An application, hosted service, or automated tool that accesses or modifies resources needs an identity created. This identity is known as a service principal. For security reasons, it's always recommended to use service principals with automated tools rather than allowing them to log in with a user identity.
Read More -
Identifies more than two Microsoft Entra ID Protection alerts associated to the user principal in a short time period. Microsoft Entra ID Protection alerts are triggered by suspicious sign-in activity, such as anomalous IP addresses, risky sign-ins, or other risk detections. Multiple alerts in a short time frame may indicate an ongoing attack or compromised account.
Read More -
Detects potentially suspicious OAuth authorization activity in Microsoft Entra ID where the Visual Studio Code first-party application (client_id = aebc6443-996d-45c2-90f0-388ff96faa56) is used to request access to Microsoft Graph resources. While this client ID is legitimately used by Visual Studio Code, threat actors have been observed abusing it in phishing campaigns to make OAuth requests appear trustworthy. These attacks rely on redirect URIs such as VSCode's Insiders redirect location, prompting victims to return an OAuth authorization code that can be exchanged for access tokens. This rule may help identify unauthorized use of the VS Code OAuth flow as part of social engineering or credential phishing activity.
Read More -
Identifies when new Service Principal credentials have been added in Microsoft Entra ID. In most organizations, credentials will be added to service principals infrequently. Hijacking an application (by adding a rogue secret or certificate) with granted permissions will allow the attacker to access data that is normally protected by MFA requirements.
Read More -
Identifies rare instances of authentication requirements for Azure Entra ID principal users. An adversary with stolen credentials may attempt to authenticate with unusual authentication requirements, which is a rare event and may indicate an attempt to bypass conditional access policies (CAP) and multi-factor authentication (MFA) requirements. The authentication requirements specified may not be commonly used by the user based on their historical sign-in activity.
Read More -
Identifies an illicit consent grant request on-behalf-of a registered Entra ID application. Adversaries may create and register an application in Microsoft Entra ID for the purpose of requesting user consent to access resources. This is accomplished by tricking a user into granting consent to the application, typically via a pre-made phishing URL. This establishes an OAuth grant that allows the malicious client applocation to access resources on-behalf-of the user.
Read More -
Identifies a modification to a conditional access policy (CAP) in Microsoft Entra ID. Adversaries may modify existing CAPs to loosen access controls and maintain persistence in the environment with a compromised identity or entity.
Read More -
Identifies when a user is observed for the first time in the last 14 days authenticating using the device code authentication workflow. This authentication workflow can be abused by attackers to phish users and steal access tokens to impersonate the victim. By its very nature, device code should only be used when logging in to devices without keyboards, where it is difficult to enter emails and passwords.
Read More -
Identifies device code authentication with an Azure broker client for Entra ID. Adversaries abuse Primary Refresh Tokens (PRTs) to bypass multi-factor authentication (MFA) and gain unauthorized access to Azure resources. PRTs are used in Conditional Access policies to enforce device-based controls. Compromising PRTs allows attackers to bypass these policies and gain unauthorized access. This rule detects successful sign-ins using device code authentication with the Entra ID broker client application ID (29d9ed98-a469-4536-ade2-f981bc1d605e).
Read More