Suspicious Intune API Activity by Service Principals

This rule identifies suspicious activity within Microsoft Intune by focusing on sensitive operations, broad assignments, and actions performed by API actors (Service Principals) without an associated human User Principal Name (UPN). It specifically looks for operations like creating, adding, assigning, or updating DeviceManagementScripts, DeviceShellScripts, Win32LobApp, DeviceConfiguration, DeviceCompliancePolicy, EndpointSecurity, SecurityBaseline, ConfigurationPolicies, or GroupPolicyConfigurations. The rule also flags broad assignments targeting 'All Devices', 'All Users', 'allDevices', or 'allLicensedUsers'. The primary goal is to detect potential abuse of over-permissioned Graph API applications by attackers to bypass MFA and deploy malicious Mobile Device Management (MDM) commands or configurations.