splunk-security_content/detections/cloud/o365_disable_mfa.yml

name: O365 Disable MFA
id: c783dd98-c703-4252-9e8a-f19d9f5c949e
version: 1
date: '2022-02-03'
author: Rod Soto, Splunk
status: production
type: TTP
description: This search detects when multi factor authentication has been disabled,
  what entitiy performed the action and against what user
data_source: []
search: '`o365_management_activity` Operation="Disable Strong Authentication." | stats
  count earliest(_time) as firstTime latest(_time) as lastTime by UserType Operation
  UserId ResultStatus object | rename UserType AS user_type, Operation AS action,
  UserId AS src_user, object AS user, ResultStatus AS result | `security_content_ctime(firstTime)`
  | `security_content_ctime(lastTime)` | `o365_disable_mfa_filter`'
how_to_implement: You must install the Splunk Microsoft Office 365 add-on. This search
  works with o365:management:activity
known_false_positives: Unless it is a special case, it is uncommon to disable MFA
  or Strong Authentication
references:
- https://attack.mitre.org/techniques/T1556/
tags:
  analytic_story:
  - Office 365 Detections
  asset_type: Office 365
  confidence: 80
  impact: 80
  message: User $src_user$ has executed an operation $action$ for user $user$
  mitre_attack_id:
  - T1556
  observable:
  - name: user
    type: User
    role:
    - Victim
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Operation
  - UserType
  - user
  - status
  - signature
  - dest
  - ResultStatus
  risk_score: 64
  security_domain: threat
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1556/o365_disable_mfa/o365_disable_mfa.json
    sourcetype: o365:management:activity
    source: o365