CMMC Level 2 Practice 3.1.9: Provide privacy and security notices consistent with applicable CUI rules

To meet CMMC Level 2 Practice 3.1.9, you must present privacy and security notices to users (and other relevant parties) that match the rules for handling CUI in your environment and systems. Operationally, this means you publish, display, and maintain consistent banners and notices at access points to CUI systems, then retain evidence that they exist, are approved, and stay current. ¹

Key takeaways:

• Post user-facing privacy/security notices (banners) wherever users access CUI systems (interactive logons, portals, remote access, and apps) and align the content to your CUI handling rules. ²
• Treat notices as a controlled artifact: owner, approval, versioning, change triggers, and periodic validation that banners remain deployed. ³
• Auditors will expect screenshots, configurations, and change records that prove notices are implemented and maintained, not just written in policy. ³

CMMC Level 2 Practice 3.1.9 is easy to underestimate because it sounds like “put up a banner.” Assessors usually treat it as a basic safeguard: if users are not clearly notified about privacy and security expectations at the moment of access, you lose a practical control point for acceptable use, consent-to-monitoring, and proper handling of sensitive data. The requirement is mapped to NIST SP 800-171 Rev. 2 control 3.1.9 and is part of the access control family in CMMC Level 2. ⁴

For operators, the win condition is straightforward: you can point to each in-scope access path to CUI (workstations, VDI, VPN, web apps, admin consoles, cloud tenants) and show a consistent, approved notice that reflects your CUI rules. Then you can show it stays deployed through change management, periodic checks, and evidence retention that survives staff turnover and tool changes. ³

This page is written for a Compliance Officer, CCO, or GRC lead who needs to assign ownership, drive implementation with IT, and package evidence for a CMMC Level 2 assessment without turning this into a quarter-long policy rewrite. ³

Regulatory text

Excerpt (as provided): “CMMC Level 2 practice mapped to NIST SP 800-171 Rev. 2 requirement 3.1.9 (Provide privacy and security notices consistent with applicable CUI rules).” ⁵

What the operator must do:
You must ensure users receive clear privacy and security notices that are consistent with the rules that apply to Controlled Unclassified Information (CUI) in your environment. Practically, this is implemented as system use notifications (often login banners) and supporting notices at key access points, backed by governance so the notice text stays accurate as systems and CUI rules change. ¹

Plain-English interpretation (what this really requires)

This practice requires two things:

1. Users see a notice at the time of access to in-scope systems: it tells them the system is for authorized use, activity may be monitored, and rules apply to handling CUI.
2. The notice matches your actual CUI rules and procedures (for example, how users should label, store, transmit, or limit sharing of CUI). If your banner claims one thing but your documented CUI handling standard says another, assessors will treat the notice as unreliable. ²

Think of it as a “point-of-use control.” Policies live in a repository; notices sit where mistakes happen.

Who it applies to

Entities: Defense contractors and other federal contractors handling CUI that are targeting or required to meet CMMC Level 2. ⁶

Operational scope:

• Systems that process, store, or transmit CUI, including endpoints, servers, virtual desktops, and cloud services inside the CUI boundary. ²
• User access paths into those systems, such as Windows/macOS logon, SSH, privileged admin consoles, VPN portals, VDI gateways, SSO login pages for CUI apps, and managed SaaS tenants in the CUI enclave. ²
• Users and admins (employees, contractors, and other authorized users) who can access CUI systems. ²

If a third party has interactive access into your CUI environment (for example, MSP support into enclave systems), your notice strategy must still work for their access path. ²

What you actually need to do (step-by-step)

1) Assign an owner and create a control card (runbook)

Create a one-page “control card” that documents:

• Objective: privacy/security notices consistent with CUI rules
• Owner: typically GRC (content) + IT/security engineering (deployment)
• Systems in scope: list the interactive access points to CUI systems
• Triggers: new system onboarding, identity change, domain migration, VDI refresh, new CUI handling rule, merger/acquisition
• Evidence bundle and storage location
  This makes the practice auditable and repeatable. ³

2) Inventory all interactive logon/access points in the CUI boundary

Build a simple table (even a spreadsheet) with:

• System/app name
• Access method (local logon, VPN, web portal, SSH, SaaS)
• Auth front door (AD, Entra ID, IdP, local)
• Banner/notice method (GPO, MDM profile, SSHD config, VPN portal message, app login page text)
• Owner and technical implementer This inventory is what keeps you from missing “one weird admin console” that an assessor will ask about. ²

3) Draft notice text that matches your CUI rules (and get approval)

Write notice content that is:

• Clear (plain language)
• Consistent with your CUI handling policy and procedures
• Appropriate to the system context (general user vs privileged admin) Route it through your normal policy/standard approval path (security leadership + legal/privacy as appropriate). Keep the approval record. ²

Practical tip: maintain two variants:

• Standard user notice (workstations, VDI, VPN, apps)
• Privileged/admin notice (admin consoles, jump hosts, bastions)
  Both should align to the same CUI rules but can be tailored for admin activity and heightened monitoring language. ²

4) Deploy notices through centralized configuration, not manual touch

Pick the right mechanism per access point:

• Windows logon banner via GPO / Intune (as applicable)
• macOS banner via MDM configuration
• SSH banner via /etc/issue.net and sshd_config
• VPN portal and client splash message via VPN platform settings
• SSO/app login page notice where supported Document exactly where the setting lives and who can change it. ³

5) Validate deployment and capture evidence

For each access point, capture:

• Screenshot of the banner at login (or equivalent)
• Screenshot/export of the configuration setting
• System list showing the policy applied (for example, GPO scope, MDM device group) Store evidence in an assessment-ready location with version tags tied to the notice text version. ³

6) Add change control and “control health checks”

Operationalize maintenance:

• Tie banner text updates to changes in CUI rules, identity platforms, or enclave boundary changes.
• Run a recurring control check: sample systems and confirm the notice still appears and matches the current approved text.
• Track findings to closure with dates, owners, and validation notes. ³

If you use Daydream to manage your control library and evidence bundles, this is a good candidate for a lightweight workflow: banner text as a controlled document, system inventory as the system-of-record, and recurring check tasks that prompt evidence refresh before assessments. ³

Required evidence and artifacts to retain

Use this as your minimum evidence bundle:

• Approved notice text (versioned) with approver names/roles and approval date
• System/access-point inventory for the CUI boundary showing where notices are deployed
• Technical configuration proof per platform (policy setting screenshots, exports, config snippets)
• User-facing proof (screenshots showing what a user sees at logon/access)
• Change records for updates to the notice text and deployment configurations
• Control health check results (sampling notes, exceptions, remediation tickets, closure validation) ³

Retention duration is not specified in the provided sources for this practice; keep artifacts consistent with your organization’s assessment readiness and contractual obligations. ³

Common exam/audit questions and hangups

Assessors and customer auditors tend to press on these points:

• “Show me the banner” for each access method (VPN, VDI, SaaS admin console), not just Windows endpoints. ³
• “How do you know it’s deployed everywhere?” Expect to show scoping (GPO/MDM targeting, device groups, enclave membership). ³
• “Who approves text changes?” They will look for governance, not ad hoc edits by IT. ³
• “Does the notice match your CUI rules?” They may cross-check against your CUI handling procedures and training language. ²

Hangup to avoid: relying on a general corporate “Acceptable Use Policy” link in an intranet page without a point-of-access notice for the CUI system. ²

Frequent implementation mistakes (and how to avoid them)

1. Notice exists in policy, not on systems.
   Fix: make the inventory of access points the authoritative checklist; require evidence per row. ³

2. Banners are inconsistent across platforms.
   Fix: maintain a controlled “golden text” and map deployment methods back to that version. ³

3. Admin paths are missed.
   Fix: explicitly include jump hosts, bastions, hypervisor consoles, cloud tenant admin portals, and SSH entry points in scope review. ²

4. Text overpromises or conflicts with actual practice.
   Fix: align wording to what you truly do (monitoring, access restrictions, CUI handling rules) and update it through change control when practice changes. ²

5. No operational cadence.
   Fix: add recurring control health checks and record results; don’t wait for assessment season. ³

Enforcement context and risk implications

No public enforcement cases were provided in the source catalog for this specific practice, so you should frame risk in assessment and contracting terms rather than penalties. ³

Where this fails in practice:

• It creates an easy “paper vs reality” finding: policy says users are notified, but the system experience shows no notice. ³
• It weakens your position in insider misuse or policy violation scenarios, because users can argue they were not notified at the point of access. Keep the notice present and consistent. ²

Practical 30/60/90-day execution plan

You asked for speed and operationalization; below is a time-boxed plan. Treat timeframes as planning guidance, not a regulatory requirement. ³

Days 1–30: Establish control design and scope

• Name control owner and technical implementers; publish the control card/runbook. ³
• Build the in-scope access-point inventory for the CUI boundary. ²
• Draft notice text variants; route for approval; assign version number. ²

Days 31–60: Deploy and collect baseline evidence

• Implement banners across priority entry points (endpoints, VPN/VDI, privileged access paths). ³
• Capture configuration exports and “what users see” screenshots for each access point. ³
• Open remediation tickets for gaps (systems that cannot display a banner, mis-scoped policies, exceptions). ³

Days 61–90: Stabilize operations and make it audit-proof

• Add banner deployment checks to onboarding for new systems and identity changes. ³
• Run the first control health check; document results and closures. ³
• Package an assessor-ready evidence folder organized by access point, with the approved notice version at the top. ³

Requirement-owner checklist (quick operational view)

• Approved notice text exists and matches your CUI rules. ²
• Every interactive access path into the CUI boundary shows a notice. ²
• Evidence includes both configuration proof and user-facing proof. ³
• Change control and recurring health checks are operating with records. ³

Frequently Asked Questions

Do we need a login banner on every system, or is a policy link enough?

For this practice, assessors typically expect a point-of-access notice for in-scope CUI systems, not just a policy stored elsewhere. Use a banner/notice wherever users authenticate or access CUI workflows. ¹

What systems count as “in scope” for notices?

Systems that process, store, or transmit CUI are in scope, and so are the access paths into them (VPN, VDI, web portals, admin consoles). Start from your CUI boundary and enumerate interactive entry points. ²

Can we use the same banner for corporate and CUI environments?

You can, but only if the text is consistent with the CUI rules that apply where it’s shown. If the corporate banner lacks CUI handling language that your procedures require, publish a CUI-specific variant for the enclave. ²

How do we handle SaaS apps that don’t support a configurable login banner?

Document the limitation, then implement the nearest equivalent notice point the platform supports (for example, SSO portal notice, in-app splash notice, or an access-gating page). Keep evidence of the constraint and the compensating implementation. ³

Who should approve the banner text?

Treat it like a controlled compliance artifact: security/GRC owns content, IT owns deployment, and legal/privacy should review if the text addresses monitoring or privacy notices. Retain the approval record as evidence. ³

What evidence is most persuasive in a CMMC assessment?

A per-access-point evidence bundle wins: approved text, deployment configuration proof, and a screenshot showing what the user sees. Pair that with a current inventory and a health check record. ³

Footnotes

1. NIST SP 800-171 Rev. 2; DoD CMMC Program Guidance

2. NIST SP 800-171 Rev. 2

3. DoD CMMC Program Guidance

4. NIST SP 800-171 Rev. 2; 32 CFR Part 170

5. NIST SP 800-171 Rev. 2; DoD CMMC Program Guidance; 32 CFR Part 170

6. 32 CFR Part 170; DoD CMMC Program Guidance