NIST Cybersecurity Framework (CSF) Skill

CSF 2.0 Structure — The Six Functions

CSF 2.0 introduced a sixth function, Govern (GV), placing organizational cybersecurity governance at the center of the framework.

Consult references/csf-20-functions-categories.md for the complete list of all categories and subcategories with IDs.

Core Concepts

Tiers (1–4)

Implementation Tiers describe the degree to which an organization's cybersecurity risk management practices exhibit the characteristics defined in the framework. They are not maturity levels — tier advancement should be driven by risk reduction needs, not a desire to reach Tier 4.

Tiers apply to three dimensions: Risk Management Process, Integrated Risk Management Program, and External Participation.

Consult references/csf-implementation-tiers.md for detailed tier descriptions and advancement guidance.

Profiles

A CSF Profile describes the alignment between an organization's cybersecurity activities and outcomes, business requirements, risk tolerance, and resources.

• Current Profile: The cybersecurity outcomes currently achieved
• Target Profile: The desired cybersecurity outcomes to achieve based on business goals and risk appetite
• Gap: The delta between Current and Target — this drives the prioritised action plan

Profiles are typically expressed as a table of subcategories rated against their current and target states (e.g., Not Implemented / Partial / Largely Implemented / Fully Implemented).

Core Workflows

1. Gap Assessment

When asked to perform or help with a gap assessment:

1. Ask for: CSF version, industry/sector, organisation size, any known Crown Jewels or high-risk areas
2. Produce a table covering all six functions, with categories and subcategories
3. For each subcategory: Current State, Target State, Gap, Priority (High/Medium/Low)
4. Summarise critical gaps by function and recommend a prioritised remediation order
5. Offer to generate an Implementation Roadmap

Current State definitions:

• ✅ Fully Implemented — control/practice is in place, documented, and operating effectively
• 🟡 Partially Implemented — some evidence exists, inconsistently applied, or gaps remain
• ❌ Not Implemented — no evidence of implementation
• N/A — not applicable to this organisation's context with documented rationale

2. Profile Creation

When asked to build an organisational profile:

1. Identify the business context: industry, mission, legal/regulatory obligations, and key assets
2. Define Risk Tolerance: risk appetite statements per function
3. Map regulatory/contractual requirements to relevant subcategories
4. Build Current Profile (assessed state) and Target Profile (desired state)
5. Highlight subcategories where regulatory or legal obligations create mandatory target states

Profile table format:

3. Implementation Roadmap

When asked to build an implementation plan:

1. Input: completed gap assessment or Target Profile
2. Prioritise gaps using: Risk Reduction Value × Effort (Low/Medium/High)
3. Group actions into phases (typically 30/60/90-day quick wins + 6/12-month strategic)
4. For each action: Subcategory ID | Action | Owner | Effort | Risk Reduction | Timeline
5. Note interdependencies (e.g., GV.RM must precede ID.RA; ID.AM must precede PR.AA)

Key sequencing logic:

• Phase 1 prerequisites: GV.OC (context), GV.RM (risk strategy), ID.AM (asset inventory), ID.RA (risk assessment) — nothing else is meaningful without these
• Phase 2: PR controls (protection measures) based on Phase 1 risk priorities
• Phase 3: DE and RS controls — detection and response capabilities
• Phase 4: RC controls + continuous improvement loop back to GV

4. Cross-Framework Mapping

When asked to map CSF to other frameworks:

• Read references/csf-20-functions-categories.md for subcategory IDs
• Common mappings:

5. Policy Generation

When generating policies or documents aligned to CSF:

• Always include: Purpose, Scope, Policy Statement, Roles & Responsibilities, Procedures, Review Cycle, Mapping to CSF Subcategory IDs
• Include a document control block: Version | Author | Approved By | Date | Next Review

CSF-aligned policy types:

CSF 2.0 vs CSF 1.1 — Key Differences

Consult references/csf-10-to-20-mapping.md for a detailed migration guide from CSF 1.1 to 2.0.

Sector-Specific Guidance

Different sectors have developed Community Profiles built on CSF. When the user's industry is known, tailor guidance accordingly:

Reference Files

Load the appropriate reference file based on the task:

• references/csf-20-functions-categories.md — All 6 functions, categories, and subcategories with IDs and descriptions (CSF 2.0)
• references/csf-10-to-20-mapping.md — CSF 1.1 → 2.0 migration guide, subcategory mapping, and change log
• references/csf-implementation-tiers.md — Full tier definitions with advancement criteria and diagnostic questions

When to load reference files:

• User asks about a specific subcategory or category → load csf-20-functions-categories.md
• User asks about CSF 1.1 differences or is transitioning → load csf-10-to-20-mapping.md
• User asks about tiers or maturity → load csf-implementation-tiers.md
• Performing a full gap assessment → load csf-20-functions-categories.md
• Cross-framework mapping → load csf-20-functions-categories.md

Disclaimer

Outputs from this skill provide informational guidance based on NIST CSF 2.0 (NIST, February 2024) and CSF 1.1 (NIST, April 2018) — both freely available public frameworks. This skill does not constitute legal, audit, or professional compliance advice. Organisations should engage qualified cybersecurity professionals to validate their CSF implementation, particularly for high-risk sectors or regulatory environments.