Entra ID OAuth Device Code Grant by Microsoft Authentication Broker
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…
Description
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).
Detection logic
Its licence does not clear it for publishing here
Sunturai publishes a detection's own text where the licence it arrived under has been reviewed and permits it, and Elastic License 2.0 has not. The query as its source wrote it, its canonical form and the hash that pins this revision are in the workspace record.
Detection requirements
- Platform
- ContainersESXiIaaSIdentity ProviderLinuxmacOSNetwork DevicesOffice SuiteSaaSWindows
The rule states no platform. This is derived from the 3 ATT&CK techniques it maps to.
- Log source category
- event_index
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| dirkjanm.io/assets/raw/Phishing%20the%20Phishing%20Resistant.pdf | Only this detection cites it |
| learn.microsoft.com/en-us/azure/azure-monitor/reference/tables/signinlogs | 2 |
| learn.microsoft.com/en-us/troubleshoot/azure/entra/entra-id/governance/verify-first-party-apps-sign-in | 2 |
From the source
- At source
- Open at source
- Upstream identifier
- a83b3dac-325a-11ef-b3e6-f661ea17fbce
- Tagged by the source as
- Data Source: AzureData Source: Azure Activity LogsData Source: Microsoft Entra IDDomain: CloudDomain: IdentityNoise: LowPerformance: FastPlatform: AzurePlatform: Entra IDProfile: RecommendedResources: Investigation GuideRule Type: Custom Query (KQL)Tactic: Initial AccessThreat: Device Code PhishingUse Case: Identity and Access Audit
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Sep 20, 2026
- Version
- 3