Google Workspace User Ou Changed

// Copyright 2023 Google LLC. Licensed under Apache-2.0.

rule google_workspace_user_ou_changed {

  meta:
    author = "Google Cloud Security"
    description = "Identifies when a Google Workspace user account is moved between Organizational Units."
    rule_id = "mr_e265b499-9a83-4e7d-acf8-ae7674e1c743"
    rule_name = "Google Workspace User Ou Changed"
    mitre_attack_tactic = "Persistence"
    mitre_attack_technique = "Account Manipulation: Additional Cloud Roles"
    mitre_attack_url = "https://attack.mitre.org/techniques/T1098/003/"
    mitre_attack_version = "v13.1"
    type = "Alert"
    data_source = "Workspace Activity"
    severity = "High"
    priority = "High"

  events:
    $ws.metadata.vendor_name = "Google Workspace"
    $ws.metadata.product_name = "admin"
    $ws.metadata.product_event_type = "MOVE_USER_TO_ORG_UNIT"
    $ws.security_result.category_details = "USER_SETTINGS"

  outcome:
    $risk_score = max(70)
    $mitre_attack_tactic = "Persistence"
    $mitre_attack_technique = "Account Manipulation: Additional Cloud Roles"
    $mitre_attack_technique_id = "T1098.003"
    $event_count = count_distinct($ws.metadata.id)
    $principal_ip = array_distinct($ws.principal.ip)
    $principal_country = array_distinct($ws.principal.ip_geo_artifact.location.country_or_region)
    $principal_state = array_distinct($ws.principal.ip_geo_artifact.location.state)
    $principal_user_emails = array_distinct($ws.principal.user.email_addresses)
    $target_user_emails = array_distinct($ws.target.user.email_addresses)
    $principal_user_id = $ws.principal.user.userid
    $old_org_unit_name = $ws.about.labels["org_unit_name"]
    $new_org_unit_name = $ws.target.user.attribute.labels["new_value"]

  condition:
    $ws
}