Artifact GuideEU

NIS2 Article 21 Gap Assessment Workflow

Map existing cybersecurity controls to Article 21 risk-management measures, identify missing evidence, and assign owners for remediation and management review.

Pair this workflow with the NIS2 Directive, Commission Implementing Regulation (EU) 2024/2690 where it applies, and ENISA implementation guidance.

Author
Sorena AI
Published
May 9, 2026
Updated
Jul 24, 2026
Sections
5

Structured answer sets in this page tree.

Primary sources
4

Cited legal and guidance references.

Publication metadata
Sorena AI
Published May 9, 2026
Updated Jul 24, 2026
Overview

This workflow helps security, legal, risk, procurement, and operations teams assess gaps in the required by NIS2 Article 21. Confirm the legal entity, service, Member State rule, and proportionality context first; then map current controls and operating evidence to all ten Article 21(2) areas, assign remediation and risk-acceptance owners, and set reassessment triggers.

Section 1

Start with scope and proportionality

Confirm whether the legal entity, service, country implementation, sector, and size or regardless-of-size rule bring the activity within NIS2 before scoring controls. Article 21 applies to essential and important entities, but Member State implementation and equivalent sector-specific Union rules can affect which requirements and evidence requests govern a particular service.

For the gap assessment, record the risk context that Article 21 uses: state of the art, relevant European and international standards where applicable, cost of implementation, entity size, exposure to risk, and the likelihood and severity of incidents.

  • Identify the entity type, relevant Annex I or Annex II sector, Member State implementation route, and service boundary being assessed.
  • Separate EU-level Article 21 requirements from local supervisory forms, registrations, portals, or templates.
  • Write down why each control is proportionate for the assessed service, not just whether a policy exists.
  • Flag any cross-border service, supplier dependency, or critical system that may change the risk treatment decision.
Section 2

Map Article 21(2) measure areas to current controls

Use Article 21(2) as the control taxonomy for the first pass. Each row should name the current control, owner, system or process covered, evidence location, gap rating, and remediation action.

Do not collapse supplier security, incident handling, access control, cryptography, and business continuity into one generic security-policy row. Article 21 expects coverage across multiple technical, operational, and organisational measure areas.

  • Risk analysis and information system security: risk methodology, risk criteria, risk register, treatment plan, and management acceptance of residual risk.
  • Incident handling: procedures for detecting, analysing, containing, responding to, recovering from, documenting, and reporting incidents.
  • Business continuity and crisis management: backup management, disaster recovery, continuity plans, and crisis roles.
  • Supply chain and acquisition security: direct supplier and service-provider risks, secure development, vulnerability handling, and disclosure.
  • Effectiveness, hygiene, cryptography, HR security, access control, asset management, authentication, and secure communications: test evidence, training records, policy reviews, logs, inventories, and exceptions.
Section 3

Use the implementing regulation carefully

Commission Implementing Regulation (EU) 2024/2690 gives directly applicable technical and methodological requirements for the provider types listed in its Article 1: DNS services, TLD registries, cloud computing, data centres, content delivery networks, managed and managed security services, online marketplaces, online search engines, social networking service platforms, and trust services. It also specifies significant-incident cases for those providers. For another NIS2 entity, the regulation is a comparator, not a binding control catalogue for that entity.

When it applies, align the gap assessment to the regulation's annexed requirements and ENISA's evidence examples. For other NIS2 entities, record the national rule or supervisory expectation that turns Article 21 into a concrete control requirement.

  • Check whether the assessed service is a DNS service, TLD registry, cloud computing service, data centre service, CDN, managed service, managed security service, online marketplace, online search engine, social networking service platform, or trust service.
  • If the implementing regulation applies, map each relevant annex requirement to a control, evidence item, gap, owner, and remediation due date.
  • If it does not apply, avoid presenting the regulation as binding for the entity; use it only as a clearly labelled comparator and add the controlling national source where available.
  • For a provider within the regulation's scope, record the reason whenever an annex requirement expressly qualified by "where appropriate", "where applicable", or "to the extent feasible" is treated as not appropriate, applicable, or feasible. Where size prevents implementation and the provider uses a suitable compensating measure as described in recital 5, record that measure. Do not use that mechanism to erase one of Article 21(2)'s ten minimum measure areas.
Section 4

Evidence fields for each gap row

Each assessment row should let a reviewer trace the requirement to the actual control, proof, owner, and decision on residual risk. A maturity score without that traceability is incomplete.

Use evidence that shows the measure is in place and maintained. ENISA examples include documented frameworks, risk assessments, treatment plans, approval records, procedures, logs, organisational charts, and review change logs, depending on the requirement being assessed.

  • Requirement reference: Article 21(2) point, implementing-regulation annex point where applicable, and national source if the local rule adds detail.
  • Current-state evidence: policy, procedure, register, ticket, audit result, test result, training record, supplier assessment, representative log sample, asset inventory, or approval record, with the covered service and review period identified.
  • Gap statement: missing control, weak evidence, unclear owner, outdated review, unsupported exception, or unaccepted residual risk.
  • Remediation owner: the person or team able to change the system, contract, process, training, or evidence repository.
  • Review trigger: significant operational change, risk change, incident, supplier change, audit finding, authority request, or scheduled review.
Section 5

Close the assessment with management visibility

Article 20 links Article 21 measures to management-body approval, oversight, training, and potential liability under Member State law. The close-out package should therefore be ready for management review, not only security-team tracking.

Before closing the assessment, confirm that residual risks have been accepted through the entity's governance process, that necessary appropriate and proportionate corrective measures are tracked without undue delay when the entity finds non-compliance with Article 21(2), and that the evidence can be retrieved for the competent authority. Customer or auditor requests may call for a separate, appropriately redacted evidence set.

What should a NIS2 Article 21 gap assessment produce?

It should produce a control-to-requirement map, evidence list, gap register, remediation owner map, residual-risk acceptance record, and review trigger list for the assessed service or entity.

Can ENISA guidance replace the NIS2 Directive or national implementation law?

No. ENISA guidance is useful for implementation and evidence examples, but the binding source remains the NIS2 Directive, applicable implementing regulation, and the relevant Member State implementation or supervisory requirements.

Does Implementing Regulation (EU) 2024/2690 apply to every NIS2 entity?

No. It applies to the provider types listed in its Article 1, including DNS, TLD registry, cloud, data centre, content delivery network, managed service, managed security service, specified online-platform, and trust-service providers. Other NIS2 entities should assess Article 21 against applicable national law and sector rules; they may use the regulation as a labelled comparator, but not present it as binding on them.

  • Summarise open Article 21 gaps by risk, impacted service, owner, and remediation status.
  • Escalate residual-risk acceptance to the management body or accountable risk owner identified in the governance process.
  • Track corrective measures separately from evidence-cleanup tasks so implementation risk is visible.
  • Keep the final assessment pack with source citations, control mapping, evidence links, exceptions, approvals, and next review triggers.
Recommended next step

This NIS2 Article 21 workflow helps build a cited gap register

Sorena can help convert Article 21 requirements, implementing-regulation annex points, and ENISA evidence examples into control mappings, evidence requests, and management-ready remediation tracking.

Primary sources

References and citations

eur-lex.europa.eu
Referenced sections
  • Article 20 connects Article 21 measures to management-body approval, oversight, training, and liability rules.
"approve the cybersecurity risk-management measures"
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