Eliminating Custom Administrator Roles in Azure for Better Security and Governance

Overview

In Microsoft Azure, Identity and Access Management (IAM) is the foundation of cloud security. While the ability to create custom roles using Role-Based Access Control (RBAC) offers flexibility, it also introduces a critical security anti-pattern: creating custom roles that grant full, subscription-level administrative privileges. This practice, often done with good intentions, directly undermines the security and governance posture of an entire cloud environment.

These custom “super-user” roles are frequently configured with wildcard permissions (*), effectively cloning the power of Azure’s built-in “Owner” role. However, they lack the maintenance, scrutiny, and built-in safeguards provided by Microsoft. As a result, they create a class of “shadow administrators” that can operate outside of standard security monitoring, increasing the attack surface and introducing unnecessary operational risk.

This article explores the business impact of allowing custom administrator roles in your Azure subscriptions. We will define the risks, outline common scenarios that lead to their creation, and provide a high-level framework for establishing governance guardrails to prevent this dangerous practice. The goal is to enforce the Principle of Least Privilege and ensure administrative access is managed through transparent, standardized, and auditable built-in roles.

Why It Matters for FinOps

From a FinOps perspective, custom administrator roles represent a significant source of unmanaged risk and potential cost. The existence of these roles complicates governance, increases the likelihood of costly security incidents, and creates operational friction that translates directly to financial waste.

The primary business impact stems from audit and compliance failures. Major frameworks like CIS Benchmarks, PCI-DSS, and SOC 2 explicitly require strict control over privileged access. The discovery of custom admin roles during an audit can lead to findings that require expensive, time-consuming remediation efforts and can even jeopardize certification.

Furthermore, these roles create operational instability. An improperly configured custom role can lead to accidental deletion of critical infrastructure, causing downtime and revenue loss. The complexity they add to governance makes it difficult to answer a fundamental question: “Who has the keys to our kingdom?” This lack of clarity hinders accurate showback/chargeback models and obscures true operational ownership, creating a chaotic environment where waste can thrive unchecked.

What Counts as “Idle” in This Article

While this article does not focus on idle resources in the traditional sense, it addresses a form of “governance waste” embodied by custom administrator roles. For our purposes, a problematic custom administrator role is any user-defined IAM role in Azure that exhibits characteristics equivalent to the built-in “Owner” role.

Key signals of such a role include:

• Broad Scope: The role is assignable at the subscription or management group level.
• Wildcard Permissions: The role definition includes the "*" action, granting permissions across all resource types, including future services.
• Lack of Deny Rules: The role fails to include necessary NotActions that prevent destructive or sensitive operations, which are often present in well-designed built-in roles.

Essentially, any custom role that is not a standard, Microsoft-managed role but grants equivalent power is considered a high-risk configuration that must be addressed.

Common Scenarios

Organizations often create custom administrator roles to solve immediate problems, inadvertently introducing long-term risk.

Scenario 1

A team needs to grant a user broad permissions to manage resources but wants to prevent them from managing user access. They create a custom role with Actions: * and NotActions: Microsoft.Authorization/*. While this seems logical, it is a fragile solution. The * action will grant permissions to new Azure services as they are released, leading to unintended privilege escalation over time.

Scenario 2

A third-party monitoring or automation tool requires access to an Azure subscription. The vendor provides unclear instructions, so a DevOps engineer creates a custom service principal role with full administrative access to ensure the tool “just works.” This action violates the Principle of Least Privilege and grants the vendor excessive permissions, creating a significant security vulnerability if the tool or its credentials are ever compromised.

Scenario 3

An organization migrating from the classic Azure Service Manager model to Azure Resource Manager (ARM) attempts to replicate the old “Co-Administrator” role. Instead of embracing the granular RBAC model, they create a custom role that mimics the legacy, all-or-nothing permission structure. This carries forward an outdated security model and fails to leverage the improved governance capabilities of modern Azure.

Risks and Trade-offs

Eliminating custom administrator roles is essential for security, but the process must be managed carefully to avoid disrupting business operations. The primary risk of these roles is the creation of “shadow admins”—privileged accounts that are invisible to standard security audits that only scan for built-in roles like “Owner.” This violates the Principle of Least Privilege and creates persistent backdoors for attackers.

However, the main trade-off is operational stability. Simply deleting a custom role without understanding its usage can break critical applications, automated pipelines, or user workflows. A thoughtful transition plan is required to map users and service principals to appropriate built-in roles, ensuring continuity. The goal is to reduce security risk without causing self-inflicted downtime, balancing security posture with business-as-usual operations.

Recommended Guardrails

To prevent the proliferation of custom administrator roles, organizations should implement a clear set of governance guardrails.

Start by establishing a strict policy that standardizes on Azure’s built-in roles for all common administrative functions. Any request to create a new custom role should trigger a mandatory approval workflow involving security and cloud governance teams. This process must validate the business justification and ensure the requested permissions adhere to the Principle of Least Privilege.

Enforce these policies using Azure Policy to audit for and block the creation of custom roles containing wildcard permissions at the subscription scope. Implement strong tagging standards to assign clear ownership for every role, both built-in and custom. Finally, for users who genuinely require elevated access, move away from permanent assignments and leverage just-in-time (JIT) access solutions to grant temporary, auditable administrative privileges.

Provider Notes

Azure

Microsoft provides a powerful and comprehensive set of tools for managing identity and access securely. The foundation is Azure Role-Based Access Control (RBAC), which allows you to assign built-in or custom roles to users, groups, and service principals. For proactive governance, Azure Policy can be used to audit or deny the creation of overly permissive custom roles. For managing privileged access without permanent assignments, Azure AD Privileged Identity Management (PIM) is the recommended best practice, enabling just-in-time access that is time-bound and fully audited.

Binadox Operational Playbook

Binadox Insight: Custom administrator roles are a hidden liability. They often fly under the radar of standard compliance checks, creating “shadow admins” that expose your organization to significant, unmanaged risk. Eliminating them is a crucial step toward mature cloud governance.

Binadox Checklist:

• Discover: Audit all Azure subscriptions to identify custom role definitions containing wildcard permissions (*).
• Analyze: Identify all users, groups, and service principals assigned to these high-risk roles and analyze their actual usage patterns via activity logs.
• Map & Replace: For each assignment, map the required duties to the most appropriate, least-privileged Azure built-in role.
• Transition: Assign the new built-in roles, then carefully remove the custom role assignments after verifying operational continuity.
• Prevent: Implement Azure Policy to block the creation of new custom roles with administrative wildcards.
• Govern: Use Azure AD PIM for all privileged access, eliminating the need for permanent administrator assignments.

Binadox KPIs to Track:

• Number of custom roles with wildcard permissions.
• Percentage of subscription administrators using just-in-time access (PIM).
• Mean Time to Remediate (MTTR) for a newly discovered non-compliant role.
• Number of policy violations related to custom role creation.

Binadox Common Pitfalls:

• Forgetting Service Principals: Focusing only on user accounts while ignoring the risky permissions assigned to automated systems and third-party tools.
• “Lift and Shift” Remediation: Deleting a custom role and replacing it with the built-in “Owner” role without first analyzing if a less-privileged role like “Contributor” would suffice.
• Lack of Proactive Controls: Cleaning up existing roles but failing to implement preventative guardrails with Azure Policy, allowing the problem to reappear.
• Disrupting Production: Removing a custom role assignment without a proper transition plan, breaking critical applications or deployment pipelines.

Conclusion

Moving away from custom administrator roles is not just a technical task; it’s a fundamental improvement to your cloud security and governance strategy. By standardizing on Azure’s built-in roles, you leverage a permission model that is maintained, audited, and understood across the industry. This reduces your attack surface, simplifies compliance, and brings clarity to your operational model.

The next step is to initiate an audit of your Azure environment. Identify where these roles exist, understand why they were created, and begin the methodical process of transitioning to a more secure model based on least privilege and just-in-time access. This proactive effort will strengthen your security posture and build a more resilient, manageable, and cost-effective cloud infrastructure.