Suspicious SignIns From A Non Registered Device — Sigma Rule

Rule metadata and linked tags

Author: Harjot Singh, '@cyb3rjy0t'. Source status: test; severity: high. Source dates: 2023-01-10 / 2025-07-02.

{
  "product": "azure",
  "service": "signinlogs"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 05e9e37af72bfea775c76056d4ab47b1ec9386c1b5fe57233cdd3647f9585d55

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Suspicious SignIns From A Non Registered Device
id: 572b12d4-9062-11ed-a1eb-0242ac120002
status: test
description: Detects risky authentication from a non AD registered device without MFA being required.
references:
    - https://learn.microsoft.com/en-us/entra/architecture/security-operations-devices#non-compliant-device-sign-in
author: Harjot Singh, '@cyb3rjy0t'
date: 2023-01-10
modified: 2025-07-02
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.initial-access
    - attack.stealth
    - attack.t1078
logsource:
    product: azure
    service: signinlogs
detection:
    selection_main:
        Status: 'Success'
        AuthenticationRequirement: 'singleFactorAuthentication'
        RiskState: 'atRisk'
    selection_empty1:
        DeviceDetail.trusttype: ''
    selection_empty2:
        DeviceDetail.trusttype: null
    condition: selection_main and 1 of selection_empty*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://learn.microsoft.com/en-us/entra/architecture/security-operations-devices#non-compliant-device-sign-in