Microsoft 365 Exchange Transport Rule Modificationedit
Identifies when a transport rule has been disabled or deleted in Microsoft 365. Mail flow rules (also known as transport rules) are used to identify and take action on messages that flow through your organization. An adversary or insider threat may modify a transport rule to exfiltrate data or evade defenses.
Rule type: query
Rule indices:
- filebeat-*
- logs-o365*
Severity: medium
Risk score: 47
Runs every: 5 minutes
Searches indices from: now-30m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Cloud
- Microsoft 365
- Continuous Monitoring
- SecOps
- Configuration Audit
Version: 3 (version history)
Added (Elastic Stack release): 7.11.0
Last modified (Elastic Stack release): 7.12.0
Rule authors: Elastic
Rule license: Elastic License v2
Potential false positivesedit
A transport rule may be modified by a system or network administrator. Verify that the configuration change was expected. Exceptions can be added to this rule to filter expected behavior.
Investigation guideedit
The Microsoft 365 Fleet integration or Filebeat module must be enabled to use this rule.
Rule queryedit
event.dataset:o365.audit and event.provider:Exchange and event.category:web and event.action:("Remove-TransportRule" or "Disable-TransportRule") and event.outcome:success
Threat mappingedit
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Exfiltration
- ID: TA0010
- Reference URL: https://attack.mitre.org/tactics/TA0010/
-
Technique:
- Name: Transfer Data to Cloud Account
- ID: T1537
- Reference URL: https://attack.mitre.org/techniques/T1537/
Rule version historyedit
- Version 3 (7.12.0 release)
-
- Formatting only
- Version 2 (7.11.2 release)
-
- Formatting only