Potential Password Spraying of Microsoft 365 User Accounts
editPotential Password Spraying of Microsoft 365 User Accounts
editIdentifies a high number (25) of failed Microsoft 365 user authentication attempts from a single IP address within 30 minutes, which could be indicative of a password spraying attack. An adversary may attempt a password spraying attack to obtain unauthorized access to user accounts.
Rule type: threshold
Rule indices:
- filebeat-*
- logs-o365*
Severity: high
Risk score: 73
Runs every: 5 minutes
Searches indices from: now-30m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
Tags:
- Elastic
- Cloud
- Microsoft 365
- Continuous Monitoring
- SecOps
- Identity and Access
Version: 4 (version history)
Added (Elastic Stack release): 7.11.0
Last modified (Elastic Stack release): 7.14.0
Rule authors: Elastic
Rule license: Elastic License v2
Potential false positives
editAutomated processes that attempt to authenticate using expired credentials and unbounded retries may lead to false positives.
Investigation guide
editConfig
The Microsoft 365 Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.
Rule query
editevent.dataset:o365.audit and event.provider:(Exchange or AzureActiveDirectory) and event.category:authentication and event.action:("UserLoginFailed" or "PasswordLogonInitialAuthUsingPassword") and event.outcome:failure
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Credential Access
- ID: TA0006
- Reference URL: https://attack.mitre.org/tactics/TA0006/
-
Technique:
- Name: Brute Force
- ID: T1110
- Reference URL: https://attack.mitre.org/techniques/T1110/
Rule version history
edit- Version 4 (7.14.0 release)
-
-
Updated query, changed from:
event.dataset:o365.audit and event.provider:AzureActiveDirectory and event.category:authentication and event.action:UserLoginFailed and event.outcome:failure
-
- Version 3 (7.13.0 release)
-
- Formatting only
- Version 2 (7.12.0 release)
-
- Formatting only