NIST CSF 2.0 evidence at the Subcategory level — the way auditors actually read it.
NSAuditor AI EE generates NIST Cybersecurity Framework 2.0 Core (NIST CSWP 29, February 2024) pre-audit gap reports mapped at the auditor-canonical Subcategory level. Signed artifacts, RFC 3161 trusted timestamps, SHA-256 chain-of-custody, suppression workflow, honest OOS framing on Govern + Respond + Implementation Tiers — and Zero Data Exfiltration, so federal-contractor and DOD-adjacent customers can scan inside their own boundary.
NIST CSF 2.0 released February 2024 (NIST CSWP 29). Structure: 6 Functions (Govern NEW in 2.0, Identify, Protect, Detect, Respond, Recover) × ~22 Categories × ~107 Subcategories. Most-requested next framework after SOC 2 + HIPAA for federal contractors, DOD-adjacent organizations, critical-infrastructure operators, and DFARS/CMMC pre-audit preparation. NSAuditor's engine is framework-agnostic — see the SOC 2 coverage matrix and HIPAA §164.312 coverage matrix for the companion frameworks.
NSAuditor AI EE generates NIST CSF 2.0 Core Subcategory-level evidence — at the same institutional grade as SOC 2 and HIPAA.
It maps cloud infrastructure findings (AWS, Azure, GCP) and network scan results to specific Subcategory IDs (PR.AA-01, DE.CM-01, RC.RP-03, etc.), produces signed evidence artifacts (cover-page Scope Attestation, SHA-256 chain-of-custody sidecars, RFC 3161 trusted-timestamps, cryptographic suppression signing), and ships NIST reports in machine-readable form suitable for NIST-aware GRC platform ingestion.
It is not a complete NIST CSF 2.0 attestation (the Govern function is OOS-by-design except GV.SC-04 partial; the Respond function is OOS-entirely). It is not an Implementation Tier 1-4 attestation (Tiers are organizational-maturity claims; pair with Tugboat Logic / Drata NIST CSF / Vanta NIST CSF / AuditBoard). It is not a NIST SP 800-53 control attestation (NIST CSF 2.0 cites SP 800-53 as Informative References, but SP 800-53 is a separate framework planned for a future cycle). It is not a NIST AI RMF attestation (also future).
What it IS: the Subcategory-level technical-evidence layer covering Protect (PR.AA + PR.DS + PR.PS + PR.IR), Detect (DE.CM + DE.AE), Recover (RC.RP), parts of Identify (ID.AM + ID.RA), and the GV.SC-04 substrate exception — complete and auditor-ready. Compatible with operator-side NIST CSF 2.0 Profile development, DFARS/CMMC pre-audit gap analysis, and federal-contractor security-questionnaire response. Honest about what infrastructure scanning fundamentally cannot evidence (Tiers + Govern + Respond) — saves you from the textbook NIST-auditor overclaim findings.
The market split: NIST-aware GRC platforms (Tugboat Logic, Drata NIST CSF, Vanta NIST CSF, AuditBoard) automate Profile development + organizational-maturity self-assessment + policy-template workflows but lack deep cloud-infrastructure scanning at the Subcategory-evidence level. Legacy scanners (Tenable, Qualys, Rapid7) produce voluminous CVE reports but don't map findings to CSF 2.0 Subcategory IDs. NSAuditor's wedge is the bridge — deep cloud + network scanning + NIST CSF 2.0 Subcategory-mapped output + same Zero Data Exfiltration architecture used for SOC 2 + HIPAA (no cloud round-trip of scan data; air-gapped deployment supported).
Why Subcategory-level mapping
NIST CSF 2.0 Core has a 3-level hierarchy:
Function (6 — Govern, Identify, Protect, Detect, Respond, Recover) — the top-level navigational grouping.
Category (~22 — e.g., PR.AA Identity Management, DE.CM Continuous Monitoring, RC.RP Recovery Plan Execution) — the middle-level grouping.
Subcategory (~107 — e.g., PR.AA-01, DE.CM-01, RC.RP-03) — the outcome statement an auditor attaches evidence to.
NIST CSF 2.0 informative-references documentation (the NIST OLIR catalog) maps Subcategories to SP 800-53 Rev. 5 controls + CIS Critical Security Controls v8 Safeguards + ISO 27001:2022 controls — all at the Subcategory level. Auditor-canonical evidence is per-Subcategory. Category-level claims (e.g., "we cover PR.AA") don't survive institutional review; auditors will ask which Subcategories of PR.AA, with what evidence.
NSAuditor maps at the Subcategory level. Per-Subcategory fields in data/compliance/nist-csf.json:
Field
Type
Purpose
id
string
Subcategory ID in canonical CSF 2.0 form: FUNCTION.CATEGORY-SUBCATEGORY (e.g., PR.AA-01).
function
enum
One of GV / ID / PR / DE / RS / RC.
categoryCode
string
Two-letter Category code (e.g., AA, CM, RP).
subcategory
string
Two-digit Subcategory ordinal (e.g., 01, 02).
outcomeText
string
NIST's verbatim outcome statement for the Subcategory (the auditor-citation-source-of-truth).
A schema-additive-fields propagation test enforces these fields reach the rendered report (closes the "ghost-schema" class — fields declared in JSON but never surfaced to auditors).
Coverage matrix by Function
Source of truth is data/compliance/nist-csf.json; this matrix mirrors it. The anchor-drift defense test asserts every (source, titlePattern) pair in nist-csf.json exists in soc2.json (inheritance contract — closes the silent false-CLEAN class at the NIST mapping layer, parallel to HIPAA's inheritance defense).
Function
Covered
Partial
OOS
Notes
GV
0
1GV.SC-04
30
Govern function OOS-by-design (policy/strategy/governance). Single substrate-evidence exception: GV.SC-04 (suppliers known) partial via cross-account VPC endpoint inventory + backup-vault wildcard-Principal trust.
The engine emits standard render targets (Markdown for auditor distribution, HTML for browser/GRC consumption, JSON for machine ingestion, CSV for spreadsheet review). NIST CSF reports include the Implementation Tiers OOS disclaimer section between the cover-page status and per-Subcategory sections — surfaces upfront that infrastructure scanning does NOT evidence Tiers per-control.
Triple-framework: SOC 2 + HIPAA + NIST CSF in one scan
The engine is framework-agnostic. A single scan with three framework targets produces three complete evidence packs, each citing its own framework's control IDs:
Each report's per-framework citation map cites only its own framework's control IDs. SOC 2 reports never cite §164.312 or PR.AA-01. HIPAA reports never cite CC IDs or PR.AA-01. NIST reports never cite CC IDs or §164.312. Cross-framework citation-leak defense is enforced in all 3 directions by 91 net new tests across 3 new test files (added in EE 0.10.0).
The same scan, same set of cloud-API calls, same findings — three frameworks. This is the institutional value prop for organizations preparing simultaneous SOC 2 + HIPAA + NIST CSF audits (or selectively responding to RFP security questionnaires that cite different frameworks).
What you get — output artifacts
NIST CSF 2.0 reports follow the same auditor-grade artifact pattern as SOC 2 and HIPAA:
Markdown (scan_compliance_nist-csf.md) — primary auditor distribution format. Cover-page Scope Attestation, Implementation Tiers OOS disclaimer, per-Subcategory sections with covered / partial / OOS framing, audit-canonical Subcategory IDs as headings.
HTML (scan_compliance_nist-csf.html) — browser / GRC-platform render. Same content as markdown including the Implementation Tiers OOS disclaimer section (markdown + HTML parity since EE 0.10.0 reviewer-fold R-HIGH-2).
10 Subcategories are partial — the engine evidences a substrate dimension but cannot evidence the full outcome (typically because part of the outcome requires operator-side process / SBOM / RTO-RPO planning / supplier registry data the engine doesn't have). Every partial control carries a partialReason field surfacing what the engine evidences vs what the operator must supply:
SIEM/UEBA platform receiving the substrate; behavioral-analytics rules for insider-threat patterns (off-hours admin, mass data download, unusual cross-account assume-role).
Govern function — OOS-by-design (with one substrate-evidence exception)
The Govern function (NEW in NIST CSF 2.0 vs 1.1) is the policy / strategy / governance dimension of the framework: GV.OC Organizational Context, GV.RM Risk Management Strategy, GV.RR Roles, Responsibilities, Authorities, GV.PO Policy, GV.OV Oversight, and GV.SC Supply Chain Risk Management. These are governance, executive-oversight, board-level, and policy-cycle evidence streams.
30 of 31 GV Subcategories are OOS by architectural design. They require board minutes, risk-register documents, signed policies, formal supplier-risk frameworks, and organizational-charter documentation — none of which infrastructure scanning can produce. Pair NSAuditor with a NIST-aware GRC platform (Tugboat Logic, Drata NIST CSF module, Vanta NIST CSF, AuditBoard) for Govern coverage.
The single substrate-evidence exception is GV.SC-04 (Suppliers are known and prioritized by criticality) — partial via cross-account VPC endpoint inventory + backup-vault wildcard-Principal trust. The engine evidences "suppliers known" through the technical supplier-trust surface (each VPC endpoint = a cross-account or cross-service trust); the "prioritized by criticality" dimension is operator-side (TPRM data the engine doesn't have). The partial rationale surfaces this distinction explicitly in the rendered report.
This OOS-by-design framing is parallel to HIPAA §164.308 + §164.310 (administrative + physical safeguards) and SOC 2 CC1.x + CC2.x + CC3.x + CC4.x + CC5.x (governance, communication, risk assessment, monitoring activities, control activities).
Respond function — OOS-entirely
The Respond function (RS.MA Incident Management, RS.AN Incident Analysis, RS.CO Reporting and Communication, RS.MI Incident Mitigation) is entirely incident-response runbook execution evidence — post-incident reports, IR-tool logs, tabletop-exercise results, communication records to regulators / customers / law enforcement, containment / eradication action records.
All 13 RS Subcategories are OOS. Infrastructure scanning produces the inputs (the original adverse-event substrate via DE.AE-02 + the substrate findings the IR team consumes) but cannot evidence the IR-runbook execution itself. Pair NSAuditor with operator's IR platform (TheHive, IBM Resilient, Demisto/Cortex XSOAR, Splunk SOAR) + IR runbook + tabletop-exercise log archive.
This OOS-entirely framing is parallel to HIPAA §164.308(a)(6) Security Incident Procedures and SOC 2 CC7.4 (Respond to Identified Incidents) — the engine evidences the substrate that incident-response programs consume but not the response itself.
Implementation Tiers 1-4 — explicitly Out of Scope
NIST CSF 2.0 Implementation Tiers (Tier 1 Partial → Tier 2 Risk-Informed → Tier 3 Repeatable → Tier 4 Adaptive) describe the maturity of cybersecurity-risk-management practices across the enterprise. They are organizational-maturity claims at the program level — NOT per-control configuration state.
Tiers are the textbook NIST-auditor overclaim risk. If a vendor surfaces a per-control Tier claim or "we're at Tier 3" assertion based on infrastructure scanning alone, the auditor flags it immediately. Tiers require evidence streams (governance / risk-management / supplier-relationship / training program data) that no infrastructure scanner can produce. NSAuditor refuses to make per-control Tier claims by architectural design — the engine NEVER emits a Tier field per Subcategory.
Instead, NIST CSF reports include an Implementation Tiers OOS disclaimer section near the cover page (markdown + HTML render-path parity, gated on isNistCsfReport) that explicitly states what infrastructure scanning CAN and CANNOT evidence. The disclaimer cites the appropriate pairings:
AuditBoard — Enterprise GRC platform with NIST CSF module.
The honest framing is the institutional value prop. A vendor that overclaims Tiers fails NIST auditor scrutiny; a vendor that names the OOS surface upfront passes.
Type-I vs Type-II for NIST CSF 2.0
NIST CSF 2.0 does not formally use Type-I / Type-II terminology (that's SOC 2 / SSAE 18 convention). NIST CSF audits typically expect:
Point-in-time evidence — current state of Subcategory-level technical posture. NSAuditor produces this directly with scan_compliance_nist-csf.* artifacts.
Profile development — the organization's Current Profile + Target Profile + Action Plan. NSAuditor's Subcategory-level findings feed the Current Profile; Target Profile + Action Plan are operator-side (pair with GRC platform Profile workflow).
Operating effectiveness over time — does the Subcategory posture hold over an attestation window? NSAuditor's recurring-scan attestation + SLA/MTTR tracking provide the cadence proof; multi-period attestation reports cover DE.CM-01 networks-monitored cadence + PR.PS-04 log-generation cadence + RC.RP-03 backup-integrity-verification cadence dimensions.
Zero Data Exfiltration — air-gapped federal deployment
The same architectural principle that makes NSAuditor AI EE a Zero-BAA tool for HIPAA applies to NIST CSF 2.0 federal deployments: scan data never leaves customer infrastructure under any condition. Nsasoft does not see, store, or process customer cloud-API credentials, scan results, or evidence artifacts. The scanner is self-hosted; AI analysis runs locally (Ollama) or via the customer's own API keys (OpenAI, Anthropic); reports are written to the customer's local out/ directory.
This is the institutional differentiator for federal contractors + DOD-adjacent customers preparing DFARS/CMMC pre-audit. ITAR-restricted, CUI-handling, or classified-adjacent infrastructure cannot use SaaS GRC platforms for scan ingestion — scan data flowing to a SaaS vendor is itself a potential DFARS/ITAR violation. NSAuditor's air-gapped deployment is compatible with the FedRAMP / DFARS / CMMC threat model where SaaS data flow is prohibited.
NIST-aware GRC platforms (Tugboat Logic, Drata NIST CSF, Vanta NIST CSF, AuditBoard) are SaaS and pair with NSAuditor for the OOS surfaces they specialize in — Govern + Respond + Tiers — without ingesting the raw scan data or cloud credentials. The Profile-level (organizational-maturity) data they consume is sanitized policy + workflow data, not infrastructure substrate.
NSAuditor produces the Subcategory-level technical substrate evidence GRC platforms cannot. Complement, not replacement.
Legacy security scanners
Tenable, Qualys, Rapid7
CVE detection at scale
NSAuditor produces NIST CSF Subcategory-mapped evidence (the format auditors actually want) rather than raw CVE lists with no framework mapping.
NIST consulting firms
Coalfire, A-LIGN, Kratos
DFARS/CMMC audit + advisory services
NSAuditor produces the pre-audit Subcategory gap report the consultant builds the audit on top of — reduces consultant billable hours.
AWS-native NIST
AWS Audit Manager (NIST CSF framework)
Pre-built control assessments using AWS Config
AWS Audit Manager covers AWS-only and maps at the Category level (not auditor-canonical Subcategory level). NSAuditor adds Azure + GCP + on-prem + cross-cloud bucket dedup + GRC platform push + WORM evidence storage. AWS Audit Manager doesn't produce institutional-grade evidence artifacts (no RFC 3161 timestamps, no Ed25519 suppression signing, no chain-of-custody envelope).
Auditor FAQ
Does NSAuditor map at the Function, Category, or Subcategory level?
Subcategory level — the auditor-canonical granularity. Functions and Categories are navigational headers; Subcategories are the outcome statements auditors attach evidence to.
Why is the Govern function OOS-by-design?
30 of 31 GV Subcategories require policy/strategy/governance evidence streams (board minutes, risk-register documents, signed policies, supplier-risk frameworks) that infrastructure scanning cannot produce. The single substrate-evidence exception is GV.SC-04 (suppliers known) via cross-account VPC endpoint inventory + backup-vault wildcard-Principal trust.
Why is the Respond function OOS-entirely?
All 13 RS Subcategories are incident-response runbook execution evidence — post-incident reports, IR-tool logs, tabletop-exercise results. Pair with operator's IR platform (TheHive, IBM Resilient, Demisto/Cortex XSOAR, Splunk SOAR) + IR runbook + tabletop-exercise log archive.
How does NSAuditor handle NIST CSF 2.0 Implementation Tiers?
Tiers 1-4 (Partial / Risk-Informed / Repeatable / Adaptive) are organizational-maturity claims explicitly OOS. The engine NEVER emits a per-control Tier claim. Reports include a cover-page Implementation Tiers OOS disclaimer (markdown + HTML parity) naming Tugboat Logic / Drata / Vanta / AuditBoard as the appropriate pairings.
What about NIST SP 800-53 or NIST AI RMF?
Both planned. SP 800-53 Rev. 5 is already cited as Informative References on covered/partial Subcategories. AI RMF is relevant when EE plugins start covering ML/AI workloads. Neither ships today.
What's the inheritance contract with soc2.json?
Every (source, titlePattern) pair in nist-csf.json MUST exist in soc2.json (defended by tests/nist_csf_mapping_anchor_drift.test.mjs). Closes the silent false-CLEAN class at the NIST mapping layer. Parallel to HIPAA's inheritance defense (EE 0.9.0).
Can NSAuditor produce a complete NIST CSF 2.0 Profile?
Partially. NSAuditor produces the technical-substrate dimension of the Current Profile (per-Subcategory configuration state). Target Profile + Action Plan + Implementation Tier self-assessment + organizational-context + supplier-risk-prioritization data are operator-side — pair with GRC Profile workflow.
How does this support DFARS / CMMC pre-audit?
DFARS 252.204-7012 + CMMC Level 2/3 cite NIST SP 800-171 + SP 800-172 — which themselves derive from NIST CSF / SP 800-53 control families. NSAuditor's Subcategory-level NIST CSF 2.0 evidence directly informs the Current Profile dimension a DFARS/CMMC pre-audit consultant builds on top of. Air-gapped deployment is compatible with ITAR / CUI handling threat model.
Does NSAuditor cover NIST CSF 1.1?
No — explicitly only NIST CSF 2.0 (Core; NIST CSWP 29, February 2024). CSF 1.1 is superseded. The version pin is enforced in data/compliance/nist-csf.jsonversion: "2.0" and reflected in the rendered frameworkLabel.