CMMC Final Rule: What Small Defense Contractors Should Prepare in IT

The CMMC final rule increased the need for defense contractors and subcontractors to treat cybersecurity as documented operational work. Even before contract clauses create direct deadlines, small businesses can prepare the IT evidence they will likely need.

Start with asset and data scoping

Identify where federal contract information and controlled unclassified information may live: email, SharePoint, Teams, file servers, endpoints, backups, vendors, and line-of-business systems. Scope drives the control plan.

Strengthen identity controls

MFA, Conditional Access, least privilege, admin role review, account lifecycle management, and logging are foundational. Old shared accounts and unmanaged guest access create documentation and security problems.

Manage devices intentionally

Contractor environments should know which devices are encrypted, patched, supported, protected by endpoint security, and allowed to access sensitive data. Windows 10 and older Office clients should be addressed as part of readiness.

Document the evidence

Policies, access reviews, incident response plans, backup tests, user training, vendor lists, device inventory, and configuration baselines should be current enough to answer customer and assessor questions.

Use Microsoft 365 carefully

Microsoft 365 can support compliance work, but settings and licensing matter. Review retention, DLP, sensitivity labels, audit logs, external sharing, and environment type before assuming the tenant is ready.