O365 Excessive Single Sign-On Logon Errorsedit

Identifies accounts with a high number of single sign-on (SSO) logon errors. Excessive logon errors may indicate an attempt to brute force a password or single sign-on token.

Rule type: threshold

Rule indices:

  • filebeat-*
  • logs-o365*

Severity: high

Risk score: 73

Runs every: 5m

Searches indices from: now-20m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References: None

Tags:

  • Elastic
  • Cloud
  • Microsoft 365
  • Continuous Monitoring
  • SecOps
  • Identity and Access

Version: 1

Rule authors:

  • Elastic
  • Austin Songer

Rule license: Elastic License v2

Investigation guideedit

## Config

The Microsoft 365 Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.

Rule queryedit

event.dataset:o365.audit and event.provider:AzureActiveDirectory and event.category:web and o365.audit.LogonError:"SsoArtifactInvalidOrExpired"

Framework: MITRE ATT&CKTM