How to Build Security Baselines That Actually Work

Organisations often reach for well-known frameworks like the Center for Internet Security (CIS) benchmarks when they begin to harden their systems. Those frameworks do have value, but treating them as a checklist to be applied without adaptation can offer a false sense of security. Effective security baselines are not just about replication, rather, they’re about understanding the why behind every control and adapting it to your environment’s real risk profile.

Baselines should help you to articulate and automate configuration standards that reflect organisational priorities, threat models and operational realities. When implemented poorly, they fracture into noise, creating a long list of settings with no rationale, little ownership, and no assurance that they actually reduce risk.

With expert insight from Ru Campbell, one of Threatscape’s multiple in-house Microsoft MVPs, we’ll walk you through what effective baseline design truly means, why default approaches often fail, and how to make baselines work in real-world security programmes.

The Problem with Cut-and-Paste Baselines

It’s common for security teams to pull CIS benchmark configurations, import them into management tools and assume they’re “secure” by association. But a baseline comprised of hundreds of individual configuration items, created for broad applicability across many environments, is rarely optimal for a specific organisation.

A baseline is, at its core, a set of expectations: what you intend the configuration of systems to be under normal, compliant operation. Without explicit tailoring, those expectations can conflict with business needs, disable essential functionality, or create mass noise in compliance reporting. This approach turns security into an exercise in list-checking rather than risk reduction.

Framework baselines like CIS exist to organise best practices and common hardening patterns. But crucially, they’re frameworks, not finished designs. They require interpretation, selection and contextual fit to the systems and workflows you care about.

Design Baselines Around Purpose

A security baseline should answer a clear question: What does compliant look like for this asset class?

This starts by breaking down your estate into meaningful groups (servers, endpoints, specialised appliances) and documenting their operating constraints, sensitivity of the data they host, and how they are accessed. For each group, the baseline you build should:

Reflect essential controls that materially reduce attack corridors
Depend on an honest assessment of how the systems are used in production
Be supported by monitoring and reporting that shows real status rather than silence

Building a baseline is ultimately a design activity. You shape the baseline by understanding both threats and business context.

Balance Security and Usability

One of the core tensions in baseline development is that rigid enforcement often clashes with productivity. Too strict a baseline will generate alerts or blocks that appear before there is a real operational risk, and teams will learn to treat those alerts as routine noise.

For example: a desktop baseline that disables all execution of code outside Microsoft-signed binaries may frustrate development teams and lead to work-around behaviours that weaken security elsewhere.

Conversely, an effective baseline considers:

Risk Reduction Impact

Does this setting materially reduce a known threat?

Operational Tolerance

Will legitimate business processes break if this is enforced?

Observable Outcomes

Can you reliably measure whether this control is working?

Those criteria help prevent control bloat, or the accumulation of settings that feel good on paper but do nothing observable in practice. They also help to align baseline development with real risk reduction rather than theory alone.

Use Tools to Validate and Enforce

Automation and tooling are essential for turning a baseline from constrained documentation into an enforced state. Configuration management systems, device compliance engines, and policy evaluation frameworks give teams the ability to codify a baseline and continuously assess drift or compliance. Regardless of the tool, whether it’s Intune, Configuration Manager or cloud policy engines, the process should be:

Publish your baseline definitions
Deploy the baseline as an enforceable policy or compliance evaluation
Monitor compliance reports and exceptions
Investigate non-compliance trends and adjust baseline criteria where necessary

Patterns of non-compliance typically signal one of two things: either the baseline is unrealistic for its environment, or there are systemic issues like unmanaged assets that need policy or process remediation.

Document Decisions and Outcomes

A useful baseline exists in documented rationale; it doesn’t just live in a management tool. Each control that makes it into a baseline should have an associated explanation of why it matters, what threat it mitigates and what evidence you expect to see when the control succeeds.

This documentation delivers two key benefits:

It provides auditors and stakeholders with insight into why a setting exists
It supports future revision cycles when threats shift or environments evolve

Baselines without documented rationale tend to become config pollution, settings that persist long after their value has faded because no one remembers why they were applied in the first place.

Expert Iteration Rather Than Perfection

Effective baselines evolve in tandem with threats, technology changes, and usage patterns. A static baseline becomes stale quickly, whereas an iterative, evidence-driven baseline becomes a living foundation for risk control. Each revision should start with measurable outcomes from the last cycle: what worked, what didn’t and why. Using data rather than intuition to refine baselines encourages risk-focused decisions over checkbox compliance.

Designing and implementing a baseline that truly reflects your organisation’s risk priorities requires more than copying defaults. Strategic decisions about which controls matter, how they interact and how they should be monitored are hard to make in isolation.

For teams seeking tailored security guidance, Threatscape’s complimentary Microsoft Advisory Services offer expert review of your baseline and configuration strategy. Specialists assess how your current controls align with threat landscape realities, recommend targeted refinements, and help bridge the gap between theory and operational security effectiveness.

Whether you are wrestling with policy deployment, managing hybrid estates or reviewing your overall security posture, this expert perspective ensures your baselines drive measurable improvement rather than checkbox compliance.