In order for Salesforce Security Center to access a child tenant and its data you need to have a user with the correct permissions in each child tenant. Many customers would want the users in the child tenants to have the fewest number of permissions possible. Based on my investigation the user in the child tenant needs to have the following permissions as a minimum:
- API Enabled
- Manage Security Center
- View Roles and Role Hierarchy
- View Setup and Configuration
I have successfully enabled these permissions for a new user by creating a new user in the child tenant using the “Salesforce” license and the “Minimum Access – Salesforce” profile. I then created a permission set with the above mentioned permissions and assigned that permission set to the user I’m going to use to access the child tenant from the parent tenant.
I was then able to authenticate as that user when connecting to the child tenant from the parent tenant.