Microsoft 365 Exchange DKIM Signing Configuration Disabled
editMicrosoft 365 Exchange DKIM Signing Configuration Disabled
editIdentifies when a DomainKeys Identified Mail (DKIM) signing configuration is disabled in Microsoft 365. With DKIM in Microsoft 365, messages that are sent from Exchange Online will be cryptographically signed. This will allow the receiving email system to validate that the messages were generated by a server that the organization authorized and not being spoofed.
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
- Data Protection
Version: 2 (version history)
Added (Elastic Stack release): 7.11.0
Last modified (Elastic Stack release): 7.11.2
Rule authors: Elastic
Rule license: Elastic License
Potential false positives
editDisabling a DKIM configuration may be done 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 guide
editThe Microsoft 365 Fleet integration or Filebeat module must be enabled to use this rule.
Rule query
editevent.dataset:o365.audit and event.provider:Exchange and event.category:web and event.action:"Set-DkimSigningConfig" and o365.audit.Parameters.Enabled:False and event.outcome:success
Rule version history
edit- Version 2 (7.11.2 release)
-
- Formatting only