1. Add an Approval Workflow via Microsoft PIM
Privileged Identity Management (PIM) transforms static admin roles into just-in-time access, with full auditability.
To restrict Groups Admin:
- Make the role “eligible” in PIM instead of “permanent.”
- Add an approval step, so someone must approve any activation.
- Set notification alerts for any activation or assignment.
This protects against:
- Silent privilege elevation.
- Accidental or malicious role use.
- Unmonitored access to sensitive groups.
“Always assume compromise. Approval-based PIM is one of the most effective controls for limiting damage from account misuse.” — Microsoft Zero Trust Principles
You can even integrate approval flows with Microsoft Teams or ServiceNow using Logic Apps for faster, trackable responses.
2. Scope Access Using Administrative Units (AUs)
Administrative Units (AUs) enable you to segment Entra objects, such as users and groups, based on business needs, think department, geography, or role.
When you assign the Groups Admin role within an AU:
- The admin can only manage the groups inside that AU.
- They can’t view or modify groups outside their assigned scope.
- This protects shared services, sensitive groups, and executive-level access from being touched by mistake.
For example, assign your Sales Ops manager a scoped Groups Admin role for the Sales AU, and they’ll only see and manage their teams.
“AUs provide delegated administration without compromising tenant-wide visibility.” — Microsoft Docs on AUs
Pro tip: Combine this with naming policies and expiration settings to keep things clean and automated.
3. Make Sensitive Groups Role-Assignable (and Break the Backdoor)
This is the most powerful (and least known) defence.
Marking a group as role-assignable changes its governance model:
- It can only be managed via Azure RBAC with the role privileged Role admin, not by Groups Admins.
- Membership changes must be done via the Roles of Group Owner, Privileged Role Admin or Global Admin
- PIM cannot assign users to these groups unless explicitly permitted.
This means that Groups Admins cannot access it, even if they try.
Why is this useful?
- Role-assignable groups are typically tied to Azure RBAC roles (like Owner).
- These roles often grant access to resources in Azure subscriptions, Key Vaults, or privileged Roles.
- Marking the group as role-assignable de-links it from the Entra group admin experience.
“When a security group is marked as ‘isAssignableToRole=true’, it is intended for privileged access and should be treated as sensitive.” – Microsoft Azure Group Management Guide
Here’s how to create one using PowerShell:
powershell
CopyEdit
New-AzureADMSGroup -DisplayName “PrivilegedAccess-AVDAdmins”`
-SecurityEnabled $true `
-MailEnabled $false `
-IsAssignableToRole $true `
-MailNickname “PrivAVDAdmins”
Be aware: these groups cannot be nested or used for license assignment. Use them only where high-privilege access requires stricter control.
How to Monitor Groups Admin Activity
What gets measured, gets managed.
Use Microsoft Sentinel to detect and alert on:
- Assignments of the Groups Admin role.
- Activations via PIM.
- Changes to group membership in sensitive groups.
Here’s a sample KQL query:
kql
CopyEdit
AuditLogs
| where ActivityDisplayName == “Add member to group”
| where TargetResources contains “PrivilegedAccess”
| project TimeGenerated, InitiatedBy, TargetResources
You can also create a watchlist of sensitive groups and flag any changes made by users with the Groups Admin role.
Final Thoughts: Don’t Leave This Door Unlocked
The Groups Admin role is not the villain; it’s the lack of restrictions around it that creates risk.
By combining PIM approvals, AUs, and role-assignable groups, you turn a potentially dangerous role into a well-governed utility.
If you’re already using Microsoft Entra ID, you have the tools; you just need to implement them.
Need Help Getting Started?
Get in touch or follow me on LinkedIn for more identity security tips.
References:
- Microsoft Learn – Groups Administrator Role
- Microsoft Entra ID Administrative Units
- Azure Role-Based Access Control and Role-Assignable Groups
- Zero Trust Deployment Guide – Identity Pillar
- Practical365 – Scoped Groups Administration