| name | cis-azure-foundations-5.16 |
| description | Ensure 'Guest invite restrictions' is set to 'Only users assigned to specific admin roles can invite guest users' or 'No one in the organization can invite guest users' |
| category | cis-azure-foundations |
| version | 5.0.0 |
| author | cyberstrike-official |
| tags | ["cis","azure","identity","guest-invitations","external-identities","access-control"] |
| cis_id | 5.16 |
| cis_benchmark | CIS Microsoft Azure Foundations Benchmark v5.0.0 |
| tech_stack | ["azure"] |
| cwe_ids | [] |
| chains_with | ["cis-azure-foundations-5.15"] |
| prerequisites | [] |
| severity_boost | {} |
Ensure 'Guest invite restrictions' is set to 'Only users assigned to specific admin roles can invite guest users' or 'No one in the organization can invite guest users'
Description
Restrict invitations to either users with specific administrative roles or no one.
Rationale
Restricting invitations to users with specific administrator roles ensures that only authorized accounts have access to cloud resources. This helps to maintain "Need to Know" permissions and prevents inadvertent access to data.
By default the setting Guest invite restrictions is set to Anyone in the organization can invite guest users including guests and non-admins. This would allow anyone within the organization to invite guests and non-admins to the tenant, posing a security risk.
Impact
With the option of Only users assigned to specific admin roles can invite guest users selected, users with specific admin roles will be in charge of sending invitations to the external users, requiring additional overhead by them to manage user accounts. This will mean coordinating with other departments as they are onboarding new users.
Audit Procedure
This setting has 4 levels of restriction:
- Anyone in the organization can invite guest users including guests and non-admins (most inclusive),
- Member users and users assigned to specific admin roles can invite guest users including guests with member permissions,
- Only users assigned to specific admin roles can invite guest users,
- No one in the organization can invite guest users including admins (most restrictive).
Using Azure Portal
- From Azure Home select the Portal Menu
- Select
Microsoft Entra ID
- Under
Manage, select External Identities
- Select
External collaboration settings
- Under
Guest invite settings, ensure that Guest invite restrictions is set to either Only users assigned to specific admin roles can invite guest users or No one in the organization [...]
Using PowerShell
Connect-MgGraph
(Get-MgPolicyAuthorizationPolicy).AllowInvitesFrom
If the resulting value is adminsAndGuestInviters or none the configuration complies.
Expected Result
Guest invite restrictions should be set to or . PowerShell should return or .
