The Statement of Applicability (SoA) is not just a foundational document for establishing an Information Security Management System (ISMS) under ISO 27001, it is also a living document that requires regular updates to remain effective. Here’s a guide on how often the SoA should be reviewed and updated, and the triggers that necessitate these revisions.
Understanding the Dynamic Nature of the SoA
The SoA must evolve in response to changes in the organisation’s internal and external environments. Regular updates ensure that the document accurately reflects the current security controls and the risks they mitigate, maintaining the organisation's compliance with ISO 27001.
Regular Review Schedule
Annual Reviews: At a minimum, the SoA should be reviewed annually. This regular check ensures that any gradual changes, such as those in corporate policy or business processes, are reflected in the SoA.
Following an ISO 27001 Audit: After every formal audit, review the SoA to address any findings or recommendations that may have arisen. Audits often highlight potential areas for improvement that can enhance the effectiveness of your ISMS.
Triggers for SoA Updates
Several specific events can trigger the need for an immediate review and possible update of the SoA:
Security Incidents: Any security breach or incident provides a clear indication that the existing controls may not be fully effective. Analysing these incidents can lead to adjustments in the SoA to prevent future occurrences.
Changes in Compliance Requirements: Updates in legal, regulatory, or contractual obligations related to information security should prompt a review of the SoA to ensure that all new requirements are met.
Business Expansion or Restructuring: Changes such as entering new markets, introducing new products, or restructuring within the company can introduce new risks or change existing ones. The SoA should be updated to address these new risk profiles.
Technological Advances or Changes: Implementing new technology or significant updates to existing IT infrastructure can alter the risk landscape substantially. An updated SoA can ensure that controls are appropriate for the new technologies.
Feedback from Stakeholders: Inputs from employees, customers, partners, or auditors might indicate areas where the ISMS could be better aligned with business practices or security needs.
Best Practices for Updating the SoA
Document All Changes: Keep a change log for the SoA, detailing what was changed, why, and by whom. This documentation is crucial for audits and for understanding the evolution of the ISMS.
Engage Relevant Stakeholders: Ensure that changes to the SoA are discussed with and approved by key stakeholders. This engagement helps maintain alignment with business objectives and enhances the security culture.
Reassess Risk Appropriately: With every significant change, reevaluate the risk assessment to ensure it remains accurate. This reassessment should feed directly into the SoA update process.
Maintaining your Statement of Applicability is a critical task in the lifecycle of an ISMS. By ensuring it is regularly reviewed and promptly updated, organisations can not only maintain compliance with ISO 27001 but also strengthen their overall information security posture. Regular updates, driven by clear triggers and guided by best practices, ensure that the SoA remains an accurate and effective tool in the management of information security.