O365 New MFA Method Registered
The following analytic detects the registration of a new Multi-Factor Authentication (MFA) method for a user account within Office 365. It leverages O365 audit logs to identify changes in MFA configurations. This…
Description
The following analytic detects the registration of a new Multi-Factor Authentication (MFA) method for a user account within Office 365. It leverages O365 audit logs to identify changes in MFA configurations. This activity is significant as it may indicate an attacker's attempt to maintain persistence on a compromised account. If confirmed malicious, the attacker could bypass existing security measures, solidify their access, and potentially escalate privileges or access sensitive data. Immediate verification and remediation are required to secure the affected account.
Detection logic
Detection requirements
- Platform
- Identity ProviderWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- o365_update_user
Known benign triggers
- Users may register MFA methods legitimately, investigate and filter as needed.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| attack.mitre.org/techniques/T1098/005/ | 6 |
| www.csoonline.com/article/573451/sophisticated-bec-scammers-bypass-microsoft-365-multi-factor-authentication.html | 2 |
| www.microsoft.com/en-us/security/blog/2023/06/08/detecting-and-mitigating-a-multi-stage-aitm-phishing-and-bec-campaign/ | 2 |
From the source
- At source
- Open at source
- Upstream identifier
- 4e12db1f-f7c7-486d-8152-a221cad6ac2b
- Tagged by the source as
- Office 365 Persistence MechanismsO365 TenantcloudSplunk CloudSplunk EnterpriseSplunk Enterprise Securityidentity
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1