Device Registration or Join Without MFA — Sigma Rule

Rule metadata and linked tags

Author: Michael Epping, '@mepples21'. Source status: test; severity: medium. Source dates: 2022-06-28 / not supplied.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: c9924565456fb3f116d1a2344a453bdfcad32d9ccf3dea48f7a64513ac39f2f0

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: Device Registration or Join Without MFA
id: 5afa454e-030c-4ab4-9253-a90aa7fcc581
status: test
description: Monitor and alert for device registration or join events where MFA was not performed.
references:
    - https://learn.microsoft.com/en-us/entra/architecture/security-operations-devices#device-registrations-and-joins-outside-policy
author: Michael Epping, '@mepples21'
date: 2022-06-28
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.initial-access
    - attack.stealth
    - attack.t1078.004
logsource:
    product: azure
    service: signinlogs
detection:
    selection:
        ResourceDisplayName: 'Device Registration Service'
        conditionalAccessStatus: 'success'
    filter_mfa:
        AuthenticationRequirement: 'multiFactorAuthentication'
    condition: selection and not filter_mfa
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://learn.microsoft.com/en-us/entra/architecture/security-operations-devices#device-registrations-and-joins-outside-policy