Justin Ibarra
53 lines
1.8 KiB
TOML
53 lines
1.8 KiB
TOML
[metadata]
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creation_date = "2020/11/30"
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maturity = "production"
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updated_date = "2021/03/03"
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[rule]
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author = ["Elastic"]
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description = """
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Identifies when external access is enabled in Microsoft Teams. External access lets Teams and Skype for Business users
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communicate with other users that are outside their organization. An adversary may enable external access or add an
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allowed domain to exfiltrate data or maintain persistence in an environment.
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"""
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false_positives = [
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"""
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Teams external access may be enabled by a system or network administrator. Verify that the configuration change was
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expected. Exceptions can be added to this rule to filter expected behavior.
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""",
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]
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from = "now-30m"
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index = ["filebeat-*", "logs-o365*"]
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language = "kuery"
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license = "Elastic License v2"
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name = "Microsoft 365 Teams External Access Enabled"
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note = "The Microsoft 365 Fleet integration or Filebeat module must be enabled to use this rule."
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references = ["https://docs.microsoft.com/en-us/microsoftteams/manage-external-access"]
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risk_score = 47
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rule_id = "27f7c15a-91f8-4c3d-8b9e-1f99cc030a51"
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severity = "medium"
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tags = ["Elastic", "Cloud", "Microsoft 365", "Continuous Monitoring", "SecOps", "Configuration Audit"]
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timestamp_override = "event.ingested"
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type = "query"
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query = '''
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event.dataset:o365.audit and event.provider:(SkypeForBusiness or MicrosoftTeams) and
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event.category:web and event.action:"Set-CsTenantFederationConfiguration" and
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o365.audit.Parameters.AllowFederatedUsers:True and event.outcome:success
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'''
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[[rule.threat]]
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framework = "MITRE ATT&CK"
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[[rule.threat.technique]]
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id = "T1098"
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name = "Account Manipulation"
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reference = "https://attack.mitre.org/techniques/T1098/"
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[rule.threat.tactic]
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id = "TA0003"
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name = "Persistence"
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reference = "https://attack.mitre.org/tactics/TA0003/"
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