Ensuring the proper security of user-assigned managed identities in Azure involves several key strategies:
1. Implement a Tiered Administration Model: Ensure that user accounts can only access managed identities with similar permissions. Avoid allowing lower-level accounts to access identities with higher privileges[2].
2. Carefully Manage Permissions: Be cautious with the permissions granted to managed identities. Regularly audit these permissions, especially for higher privileges. Consider creating tools to report high-priority permissions assigned to apps and managed identities[2].
3. Use Role-Based Access Control (RBAC): Use RBAC to control who can assign or manage managed identities. This helps prevent unauthorized access and ensures that identities are used appropriately[3].
4. Monitor and Alert: Set up monitoring and alerting for changes in managed identity assignments. This allows you to quickly respond to unauthorized assignments[3].
5. Follow the Principle of Least Privilege: Grant managed identities only the necessary permissions to perform their tasks. Avoid granting unnecessary permissions that could increase the security risk if the identity is compromised[5].
6. Manually Manage User-Assigned Identities: Since user-assigned identities have an independent lifecycle, manually delete them when they are no longer needed. Also, ensure that role assignments are removed after deleting managed identities to avoid exceeding role assignment limits[5][6].
7. Use Security Groups and Resource Locks: Consider using security groups to reduce the number of role assignments needed. Resource locks can also help prevent accidental deletion or modification of critical resources[3].
Citations:
[1] https://learn.microsoft.com/en-us/entra/identity/managed-identities-azure-resources/how-manage-user-assigned-managed-identities
[2] https://practical365.com/heard-at-tec-mischief-managed-attacking-and-securing-azure-managed-identities/
[3] https://www.reddit.com/r/AZURE/comments/175ewbq/managed_identity_how_to_prevent_others_from_using/
[4] https://learn.microsoft.com/en-us/entra/identity/managed-identities-azure-resources/how-to-configure-managed-identities
[5] https://learn.microsoft.com/en-us/entra/identity/managed-identities-azure-resources/managed-identity-best-practice-recommendations
[6] https://www.red-gate.com/simple-talk/cloud/azure/azure-function-and-user-assigned-managed-identities/
[7] https://www.evolvesecurity.com/blog-posts/securing-azure-managed-identities
[8] https://docs.azure.cn/en-us/automation/enable-managed-identity-for-automation