Google CloudOverview
It is recommended that the principle of 'Separation of Duties' is enforced while assigning service-account related roles to users.
Rationale
The built-in/predefined IAM role Service Account Admin allows the user/identity to create, delete, and manage service account(s). The built-in/predefined IAM role Service Account User allows the user/identity (with adequate privileges on Compute and App Engine) to assign service account(s) to Apps/Compute Instances.
Separation of duties is the concept of ensuring that one individual does not have all necessary permissions to be able to complete a malicious action. In Cloud IAM - service accounts, this could be an action such as using a service account to access resources that user should not normally have access to.
Separation of duties is a business control typically used in larger organizations, meant to help avoid security or privacy incidents and errors. It is considered a best practice.
No user should have Service Account Admin and Service Account User roles assigned at the same time.
Impact
The removed role should be assigned to a different user based on business needs.
Remediation guidance
From Google Cloud Console
- Under
IAM & Admin, go toIAM - For any member having both
Service Account AdminandService Account Userroles granted/assigned, click theDeleteBin icon to remove either role from the member. Removal of a role should be done based on business requirements.
References
- https://cloud.google.com/iam/docs/service-accounts
- https://cloud.google.com/iam/docs/understanding-roles
- https://cloud.google.com/iam/docs/granting-roles-to-service-accounts
Service-wide remediation
Recommended when many resources are affected: fix the platform baseline first so new resources inherit the secure setting, then remediate the existing flagged resources in batches.
Google Cloud
Use organization or folder policies where available, shared project templates, logs and alerting baselines, and IaC modules so new resources inherit the secure setting.
Operational rollout
- Fix the baseline first at the account, subscription, project, cluster, or tenant scope that owns this control.
- Remediate the currently affected resources in batches, starting with internet-exposed and production assets.
- Re-scan and track approved exceptions with an owner and expiry date.
Query logic
These are the stored checks tied to this control.
Separation of duties is enforced while assigning service account related roles to users
Connectors
Covered asset types
Expected check: eq []
{
iamUsers(
where: {
AND: [
{
hasIAMRole_SOME: {
name: "roles/iam.serviceAccountAdmin"
}
}
{
hasIAMRole_SOME: {
name: "roles/iam.serviceAccountUser"
}
}
]
}
) {
...AssetFragment
}
}
