Entra ID OAuth Device Code Flow with Concurrent Sign-ins

Description

Identifies Entra ID device code authentication flows where multiple user agents are observed within the same session. This pattern is indicative of device code phishing, where an attacker's polling client (e.g., Python script) and the victim's browser both appear in the same authentication session. In legitimate device code flows, the user authenticates via browser while the requesting application polls for tokens - when these have distinctly different user agents (e.g., Python Requests vs Chrome), it may indicate the code was phished and redeemed by an attacker.

Detection logic

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Detection requirements

Platform: Containers ESXi IaaS Identity Provider Linux macOS Network Devices Office Suite SaaS Windows
The rule states no platform. This is derived from the 3 ATT&CK techniques it maps to.

Known benign triggers

Legitimate use of device code flow where a user authenticates via browser for a CLI tool or headless application. Common legitimate scenarios include Azure CLI, Azure PowerShell, or VS Code remote development. Review the user agent combinations - browser + known CLI tool from the same user may be expected behavior.

References

Links the source published beside this detection. Reference is the link the source wrote, unmodified. Class is decided by this catalogue from the host and path, not stated by the source. Cited by counts published detections citing the same resource, including this one, and the sources beneath it count the repositories this catalogue ingests, which is not the same as independent research.
Reference	Class	Cited by
docs.microsoft.com/en-us/azure/active-directory/reports-monitoring/reference-azure-monitor-sign-ins-log-schema	Product documentation	8
learn.microsoft.com/en-us/entra/identity/	Product documentation	3
learn.microsoft.com/en-us/entra/identity/monitoring-health/concept-sign-ins	Product documentation	6from 2 sources
www.volexity.com/blog/2025/04/22/phishing-for-codes-russian-threat-actors-target-microsoft-365-oauth-workflows/	Threat report	19
www.wiz.io/blog/recent-oauth-attacks-detection-strategies	Threat report	Only this detection cites it

Detection rules

Entra ID OAuth Device Code Flow with Concurrent Sign-ins

Description

Detection logic

Detection requirements

Known benign triggers

MITRE ATT&CK mappings

References

From the source

Licence

Authorship

Detection rules