Service principal sign-in activity is a new insight available in the Entra admin center. As explained here, it’s also possible to use PowerShell to fetch and analyze the data to derive new insights into what apps create service principals in a tenant and what organizations own the apps. Some detective work is needed to fully understand the data. That might be an ongoing task, but at least we have the data.
A reader asked how to report user and group assignments for enterprise apps. As it turns out, this isn’t particularly difficult, if you know where to look. Our script uses the Graph SDK to check service principals, filters out the apps to check, and extracts the user and group assignments before reporting what it finds.
The question of how best to block PowerShell access for Microsoft 365 user accounts deserved some consideration. The answer lies in service principals for the enterprise accounts created by Microsoft to allow PowerShell modules to authenticate with Entra ID. By restricting access to an assigned security group, you effectively block access to anyone outside that group.