New Federated Domain Added - Exchange — Sigma Rule

Rule metadata and linked tags

Author: Splunk Threat Research Team (original rule), '@ionsor (rule)'. Source status: test; severity: medium. Source dates: 2022-02-08 / not supplied.

{
  "service": "exchange",
  "product": "m365"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 978880861725b27d1461809e494fcfbbd1149595e7bf8b7f1ad24e012b08a4b2

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: New Federated Domain Added - Exchange
id: 42127bdd-9133-474f-a6f1-97b6c08a4339
related:
    - id: 58f88172-a73d-442b-94c9-95eaed3cbb36
      type: similar
status: test
description: Detects the addition of a new Federated Domain.
references:
    - https://www.fireeye.com/content/dam/fireeye-www/blog/pdfs/wp-m-unc2452-2021-000343-01.pdf
    - https://us-cert.cisa.gov/ncas/alerts/aa21-008a
    - https://www.splunk.com/en_us/blog/security/a-golden-saml-journey-solarwinds-continued.html
    - https://www.sygnia.co/golden-saml-advisory
    - https://o365blog.com/post/aadbackdoor/
author: Splunk Threat Research Team (original rule), '@ionsor (rule)'
date: 2022-02-08
tags:
    - attack.persistence
    - attack.t1136.003
logsource:
    service: exchange
    product: m365
detection:
    selection:
        eventSource: Exchange
        eventName: 'Add-FederatedDomain'
        status: success
    condition: selection
falsepositives:
    - The creation of a new Federated domain is not necessarily malicious, however these events need to be followed closely, as it may indicate federated credential abuse or backdoor via federated identities at a similar or different cloud provider.
level: medium

Original YAML and metadata in JSON

False positives

• The creation of a new Federated domain is not necessarily malicious, however these events need to be followed closely, as it may indicate federated credential abuse or backdoor via federated identities at a similar or different cloud provider.

Source references

• https://www.fireeye.com/content/dam/fireeye-www/blog/pdfs/wp-m-unc2452-2021-000343-01.pdf
• https://us-cert.cisa.gov/ncas/alerts/aa21-008a
• https://www.splunk.com/en_us/blog/security/a-golden-saml-journey-solarwinds-continued.html
• https://www.sygnia.co/golden-saml-advisory
• https://o365blog.com/post/aadbackdoor/