ISO 27001 Annex A guide

ISO 27001 Annex A 8.9: Configuration management

Define, deploy and monitor secure configuration baselines across relevant technology. This independent guide turns that purpose into practical ownership, operating evidence and auditor-ready testing.

Control
8.9
Category
Technological controls
Primary outcome
Define secure baselines, control configuration change and detect material drift.

What Control 8.9 means in practice

Define secure baselines, control configuration change and detect material drift. Test the control through the organisation's actual scope, decisions, ownership and operating records rather than relying on a policy reference alone.

For configuration management, proportional design depends on the affected services, information, people and dependencies. The evidence below should be adapted to that real boundary.

Implementation steps

  1. Step 1. Define ownership, scope and operating criteria for configuration management.
  2. Step 2. Implement operating procedure that fits the organization’s risks, services and working practices.
  3. Step 3. Integrate the activity with relevant change, exception and review processes.
  4. Step 4. Review performance and improve the arrangement when risks, technology or obligations change.

What good implementation looks like

  • drift findings resolved within risk-based targets
  • sampled systems matching approved baselines
  • baseline changes tested and approved

Implementation evidence and effectiveness evidence

Evidence the control is implemented

  • approved operating procedure
  • operational records
  • assigned ownership and approval evidence
  • sample implementation, review and exception records

Evidence the control is effective

  • drift findings resolved within risk-based targets
  • sampled systems matching approved baselines
  • baseline changes tested and approved

How an auditor may test Control 8.9

  1. Select a representative in-scope service, asset or process.
  2. Confirm the accountable owner and expected operation.
  3. Trace a recent example: A hardened server baseline is implemented as code and tested before release.
  4. Inspect the operating record and corroborating technical evidence.
  5. Compare the design with evidence that the control operated effectively.
  6. Follow an exception or adverse result through decision and closure.
  7. Review trends, metrics and improvement decisions.

Questions to prepare for

  • How is configuration management implemented in practice?
  • Who owns the activity and how are decisions approved?
  • Show me a recent example from operation through review.
  • How are exceptions, changes or overdue actions handled?

Practical examples

Example 1

A hardened server baseline is implemented as code and tested before release.

Example 2

Cloud storage configured for public access generates an alert and remediation ticket.

Example 3

Approved exceptions identify affected assets, rationale and expiry.

Illustrative decision and evidence record

Control outcomeDefine secure baselines, control configuration change and detect material drift.
Illustrative activityA hardened server baseline is implemented as code and tested before release.
Evidence sampleapproved operating procedure
Effectiveness signaldrift findings resolved within risk-based targets
Auditor questionHow is configuration management implemented in practice?
Failure to challengedocumenting configuration management without consistent operation

Reviewer note: Test configuration management with a recent real example; a current operating record normally reveals more than policy wording alone.

Useful performance and coverage measures

  • critical drift age
  • baseline coverage
  • expired configuration exceptions

Approach for smaller and mature organizations

Smaller organization

Use a clear owner, a proportionate working record, built-in platform capability and a scheduled review. Sample real activity instead of creating duplicate paperwork for configuration management.

Mature or complex organization

Define service-level ownership, automated coverage reporting, integrated workflow, risk-based exceptions and independent assurance across business units and technology platforms.

Practical implementation checklist

  • □ Define ownership, scope and operating criteria for configuration management.
  • □ Implement operating procedure that fits the organization’s risks, services and working practices.
  • □ Integrate the activity with relevant change, exception and review processes.
  • □ Review performance and improve the arrangement when risks, technology or obligations change.
  • □ Sample evidence has been checked for operation and effectiveness.
  • □ Exceptions have owners, rationale, review dates and closure evidence.

Common implementation mistakes

  • documenting configuration management without consistent operation
  • unclear ownership or review frequency
  • evidence that does not cover the full ISMS scope
  • exceptions accepted without risk-based approval or follow-up

Frequently asked questions

Must we use a specific benchmark?

No. Recognized benchmarks can inform baselines, but settings must fit the technology, use and risk.

Is a build document enough?

No. Effective configuration management also verifies deployed state and handles drift and exceptions.

How should cloud configuration be covered?

Use provider configuration, policy-as-code or posture tools proportionate to the environment and verify findings are acted upon.

Use the interactive control lookup

Open Control 8.9 in the free tool to browse connected controls and practical evidence alongside the complete reference set.

Open Control 8.9 in the Annex A lookup →