O365 Persistent Login Activity To Azure AD PowerShell App

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rule o365_persistent_login_activity_to_azure_ADPowerShell_app {

  meta:
    author = "Google Cloud Security"
    description = "Continual logins to Azure AD PowerShell app are not a security best practice, if this is observed, additional investigation is needed"
    rule_id = "mr_4e61ae7f-d9fc-4c2a-b086-69d9d50dc5cc"
    rule_name = "O365 Persistent Login Activity To Azure AD PowerShell App"
    tactic = "TA0008"
    technique = "T1021.007"
    type = "alert"
    platform = "azure"
    data_source = "o365"
    severity = "Medium"
    priority = "Medium"

  events:
    $login.metadata.event_type = "USER_LOGIN"
    $login.metadata.product_event_type = "UserLoggedIn"
    $login.metadata.product_name = "Office 365"
    $login.metadata.vendor_name = "Microsoft"
    $login.target.resource.product_object_id = "1b730954-1685-4b74-9bfd-dac224a7b894"
    $login.security_result.action = "ALLOW"
    $login.target.user.userid = $userid
    $login.metadata.event_timestamp.seconds = $time

  match:
    $userid over 24h

  outcome:
    $risk_score = 65
    $event_count = count_distinct($login.metadata.id)
    $entra_id_login_threshold = 2
    $security_summary = array_distinct($login.security_result.summary)
    $user_agent = array_distinct($login.network.http.user_agent)
    $country_region_login_attempt = array_distinct($login.principal.ip_geo_artifact.location.country_or_region)
    //added to populate alert graph with additional context
    $principal_ip = array_distinct($login.principal.ip)
    $target_user_userid = array_distinct($login.target.user.userid)

  condition:
    // Can set based on your own threshold
    #time > 1
}