CMMC Acronyms and Terms Explained: A Plain-English Guide for Defense Contractors

Jan 15
3 min read

If you are preparing for Cybersecurity Maturity Model Certification, understanding the language matters almost as much as implementing the controls. CMMC introduces a dense mix of acronyms, standards, and regulatory references that can quickly become confusing—especially for organizations encountering formal compliance for the first time.

This article explains the most important CMMC-related terms in plain English and points you directly to the official government sources that define them.

What Is CMMC?

The Cybersecurity Maturity Model Certification (CMMC) is the U.S. Department of Defense’s framework for ensuring contractors protect sensitive government information. Unlike earlier self-attestation models, CMMC requires organizations to demonstrate and verify cybersecurity practices through structured assessment.

CMMC applies to defense contractors and subcontractors that handle government data as part of DoD contracts.

CMMC Levels Explained

CMMC Level 1

Applies to organizations that handle Federal Contract Information (FCI). Level 1 focuses on basic cyber hygiene and foundational safeguards.

CMMC Level 2

Applies to organizations that handle Controlled Unclassified Information (CUI). Level 2 aligns closely with NIST SP 800-171 and introduces formal assessment requirements.

Most defense contractors fall under CMMC Level 2.

CUI (Controlled Unclassified Information)

CUI is sensitive government information that is not classified but still requires protection. Examples include technical drawings, engineering data, specifications, and certain operational communications.

Handling CUI is what triggers CMMC Level 2 requirements.

NIST SP 800-171

NIST SP 800-171 defines the security controls required to protect CUI in non-federal systems. These controls cover areas such as access control, incident response, configuration management, and audit logging.

CMMC Level 2 is largely based on these requirements but adds formal assessment and verification expectations.

DFARS 252.204-7012

This Defense Federal Acquisition Regulation Supplement (DFARS) clause requires contractors to safeguard CUI and report cyber incidents. DFARS existed before CMMC, but CMMC introduces enforcement and independent validation.

SSP (System Security Plan)

An SSP describes how your organization implements each required security control. It defines system boundaries, responsibilities, policies, procedures, and technical safeguards.

Assessors rely heavily on the SSP to understand how compliance is achieved in practice.

POA&M (Plan of Action and Milestones)

A POA&M documents known gaps in compliance, along with remediation plans and timelines. It shows that risks are identified, tracked, and actively managed.

While limited POA&Ms may be permitted in some cases, they must be realistic and well-documented.

Evidence

Evidence is the proof that controls are implemented and operating as described. This includes policies, configurations, logs, screenshots, tickets, procedures, and demonstrations.

CMMC assessments are evidence-driven, not trust-based.

Official CMMC & DoD Cybersecurity Resources

Below are the primary, authoritative sources that define CMMC requirements. These are the references assessors, auditors, and regulators rely on.

CMMC Program (DoD)

Office of the Under Secretary of Defense for Acquisition & Sustainment – CMMC https://dodcio.defense.gov/CMMC/

NIST Standards

NIST SP 800-171 https://csrc.nist.gov/pubs/sp/800/171/r2/upd1/final
NIST SP 800-171A (Assessment Guide) https://csrc.nist.gov/pubs/sp/800/171/a/final

DFARS

DFARS 252.204-7012 https://www.acquisition.gov/dfars/252.204-7012

Controlled Unclassified Information (CUI)

National Archives – CUI Registry https://www.archives.gov/cui

CMMC Accreditation & Assessments

Cyber AB (formerly CMMC-AB) https://cyberab.org

Why This Matters

Many failed or delayed CMMC efforts stem from misunderstanding terminology, scope, or evidence expectations. CMMC is not about buying tools quickly—it is about governance, repeatability, and defensible proof.

Understanding the language and the official sources is the first step toward meaningful readiness.

Disclaimer

The information contained in this communication is intended for limited use for informational purposes only. It is not considered professional advice, and instead, is general information that may or may not apply to specific situations. Each case is unique and should be evaluated on its own by a professional qualified to provide advice specifically intended to protect your individual situation. TK Compliance is not liable for improper use of this information.