13 Jul 2026CMMC Phase II suspended: no C3PAO assessments can be designated. DFARS 7012 and Rev 2 still apply.What changed, and what did not
MacZine
The MacTech Solutions Newsletter
Topic · 12 articles

CUI

Every MacZine article on CUI, newest first - written, reviewed and versioned in the open.

037Issue Nº

The FAR CUI Rule Is Coming for Contractors Who Never Saw DFARS

The proposed FAR CUI rule would put NIST 800-171 Rev 3, a 72-hour incident clock, and a new standard form into civilian agency contracts.

September 17, 2026
032Issue Nº

CUI Sprawl Is the Scope Creep Nobody Diagrams

A correctly scoped CUI enclave still leaks through tickets, meeting transcripts, and test copies. NIST 800-171 3.1.3 closes it - stricter marking can't.

September 3, 2026
031Issue Nº

What Actually Makes a File CUI

CUI is a government designation, not a judgment you make on a file's contents. How marking, derivative marking, and decontrol actually work.

September 1, 2026
029Issue Nº

Home Office CUI Scope Starts at the Kitchen Table

NIST 800-171 physical protection assumes an office, not a house. Keep CUI off the remote endpoint and most of the control problem disappears.

August 28, 2026
022Issue Nº

Can You Put CUI in an AI Tool? Read the Cloud Clause First

The DFARS clause that governs cloud service providers already answers whether CUI can go into an AI tool - most of the commercial tier fails it.

August 19, 2026
018Issue Nº

A C3PAO Validates the Evidence Problem Behind Vault-Codex

A CMMC assessor's letter of support confirms the documentation and evidence-management problem is real - and where MacTech Vault-Codex fits.

August 14, 2026
016Issue Nº

EnclaveWatch: Monitoring a CUI Vault Without Draining It

Continuous monitoring usually means shipping logs somewhere central. Inside a CUI boundary that is the one thing you should not do. EnclaveWatch inverts it.

August 12, 2026
014Issue Nº

FIPS 140-3 Is the Control That Fails Quietly

Encryption that is strong is not the same as encryption that is validated. The distinction costs 5 SPRS points and it is invisible until an assessor looks.

August 10, 2026
011Issue Nº

The 72-Hour Clock in DFARS 252.204-7012, Hour by Hour

DFARS 7012 gives you 72 hours to report a cyber incident to DoD. Walking the clock hour by hour shows where contractors actually lose the time.

August 5, 2026
010Issue Nº

Enclave or Whole Network? The Scoping Decision, Priced

Scoping CMMC Level 2 to a CUI enclave or to your whole network is a cost decision disguised as an architecture decision. Here is how the two actually compare.

August 4, 2026
003Issue Nº

Freehold: Secure Comms You Hold Outright

Peer-to-peer encrypted chat, calls and 2 GB file transfer for small DIB teams - post-quantum, air-gap ready, 800-171 evidence built in. Free, open source.

July 22, 2026
002Issue Nº

The First 90 Days of a CMMC Level 2 Program

A practitioner's sequence for the first 90 days of CMMC Level 2: scope the CUI boundary, baseline against NIST 800-171, and start evidence discipline early.

July 21, 2026