Sample rules
Entra ID Device Registration with ROADtools Default OS Build
- source: elastic
- technicques:
- T1098
Description
Identifies a Microsoft Entra ID device registration where the recorded cloud device operating system build is “10.0.19041.928” and the device display name follows the default “DESKTOP-” pattern. This combination is the default device profile that ROADtools (roadtx) uses when registering a device, and it is uncommon for the OS build to match the hardcoded value across an environment of otherwise patched hosts. Adversaries register rogue devices in Entra ID to acquire a Primary Refresh Token (PRT), establish persistence, and obtain trusted, programmatic access to the tenant. Because the OS build is a tool default, this is a high-fidelity but evadable indicator; baseline approved provisioning tooling and device naming conventions before relying on it.
Detection logic
data_stream.dataset:"azure.auditlogs" and event.action:"Add device" and
azure.auditlogs.properties.target_resources.0.modified_properties.3.new_value:*10.0.19041.928* and
azure.auditlogs.properties.target_resources.0.modified_properties.4.new_value:*DESKTOP-*
Entra ID Device with ROADtools Default OS Build (Entity Analytics)
- source: elastic
- technicques:
- T1098
Description
Identifies the first occurrence of a Microsoft Entra ID device, surfaced through the Entra ID Entity Analytics device
inventory, whose host name follows the default “DESKTOP-” pattern and whose operating system build is 10.0.19041.928.
This combination is the default device profile that ROADtools (roadtx) uses when registering a device, and the OS build
typically differs from the patched OS versions of legitimate hosts in the environment. Adversaries register rogue
devices in Entra ID to acquire a Primary Refresh Token (PRT), establish persistence, and obtain trusted, programmatic
access to the tenant. Because the OS build is a tool default, this is a high-fidelity but evadable indicator; baseline
approved device builds and naming conventions before relying on it.
Detection logic
data_stream.dataset:"entityanalytics_entra_id.device" and
event.provider:"Microsoft Entra ID" and
host.name:DESKTOP-* and host.os.version:"10.0.19041.928"