The Real Cybersecurity Challenges for Defense Contractors

Word count: ~970 Specificity markers: (2) Cost/time estimates — typical CMMC remediation costs, timeline to certification; (4) Common mistake — waiting for a contract requirement before starting preparation; (5) Decision point — whether to use an MSP, hire staff, or build a hybrid model

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Defense contractors face cybersecurity challenges that commercial businesses don't. The regulatory requirements are more specific, the threat environment is more intense, and the consequences of failure include losing contracts — not just a fine. But when contractors describe what actually makes CMMC (Cybersecurity Maturity Model Certification) compliance hard, the problems are usually more practical than technical.

This article is about the real obstacles — the ones that show up when you try to actually implement a CMMC compliance program, not just read about one.

The Resource Gap at Smaller Contractors

Most defense contractors aren't large companies with dedicated security teams. A significant portion of the Defense Industrial Base (DIB) consists of small businesses — engineering firms, specialized manufacturers, professional services companies — that may have one or two IT staff members handling everything from network maintenance to help desk support.

CMMC Level 2 requires 110 security controls. Implementing and maintaining those controls requires expertise across identity and access management, endpoint security, network architecture, log management, incident response, and policy development. That's not one person's job. It's not even comfortably two people's jobs.

The realistic paths are: hire a qualified Managed Security Service Provider (MSSP) that understands CMMC, or bring on additional qualified staff, or some hybrid. Each has tradeoffs. An MSSP that handles CMMC environments typically costs $5,000–$15,000 per month for a mid-size contractor. Hiring a full-time information systems security officer (ISSO) runs $100,000–$140,000 per year in most markets — and the candidate pool for people with CMMC experience is competitive.

Neither is cheap. But attempting to manage CMMC compliance on IT resources built for basic infrastructure support is how organizations end up with critical gaps they don't discover until their assessment.

Legacy Systems and Technical Debt

Many defense contractors have been doing defense work for decades. Their systems reflect that history: aging infrastructure that was built before current cybersecurity requirements, custom applications that can't be patched in the traditional sense, and OT (operational technology) systems — manufacturing equipment, test rigs, specialized design tools — that weren't designed with network security in mind.

Legacy systems create specific CMMC problems. Older Windows systems that can't receive security updates can't meet configuration management requirements. Industrial control systems that don't support modern authentication protocols can't implement multi-factor authentication (MFA). Applications that log nothing can't provide the audit trail that the Audit and Accountability (AU) domain requires.

The solution is rarely "replace everything." That's often cost-prohibitive and operationally disruptive. Instead, contractors typically use compensating controls — network segmentation to isolate legacy systems from CUI (Controlled Unclassified Information) environments, additional monitoring at system boundaries, and documented risk acceptance for systems that genuinely can't be remediated. This approach is legitimate, but it requires careful documentation and a clear argument for why the compensating controls adequately reduce risk. Assessors will scrutinize it.

The Gap Between Documentation and Reality

CMMC assessors evaluate controls three ways: they examine your documentation, interview your people, and test your systems. Organizations that focus exclusively on documentation — writing a thorough SSP (System Security Plan) and comprehensive policies — often discover that the documentation doesn't match reality.

The SSP says MFA is enabled for all privileged accounts. The assessor asks your IT administrator to demonstrate it, and three of the twelve admin accounts don't have MFA configured. That's a Not Met.

The policy says all CUI is stored in the designated file server. The assessor asks an engineer where they keep project files. They mention a folder on their local desktop they use for convenience. That's a Not Met.

These gaps aren't the result of malicious shortcuts — they're the natural accumulation of operational reality. Standards drift. Exceptions happen. People forget. The challenge for defense contractors is building security practices that hold up under daily operations, not just during preparation for an assessment.

The Regulatory Pace Problem

CMMC itself has changed several times since it was first introduced. Version 1.0 had five levels. CMMC 2.0 consolidated to three. The final rule implementing CMMC 2.0 came into effect in late 2024. DFARS (Defense Federal Acquisition Regulation Supplement) clause 252.204-7021, which formally requires CMMC compliance in DoD contracts, is now in full effect for new contracts.

But the regulatory environment doesn't sit still. NIST SP 800-171 Rev 3 has been published, though CMMC assessments currently evaluate against Rev 2. A future CMMC revision will incorporate Rev 3 requirements. The FAR (Federal Acquisition Regulation) CUI rule, which extends CUI protection requirements beyond DoD contracts to other federal agencies, is still being finalized.

Keeping current with what's required, what's changing, and what timeline applies to your specific contracts requires ongoing attention. Contractors who delegate this entirely to a consultant risk being surprised when requirements shift. Someone inside the organization needs to own the awareness.

The Common Mistake: Waiting for the Contract Requirement

The single most predictable way CMMC preparation goes wrong: a contractor receives a contract solicitation that includes a CMMC requirement, and that's the moment they start preparing.

Depending on their current security posture, that might mean they have six months to achieve certification before the contract award. For organizations starting from scratch, Level 2 certification typically requires 12–18 months of preparation, including gap assessment, remediation, SSP development, and C3PAO assessment scheduling. C3PAOs have limited capacity and waiting lists. Remediation of serious infrastructure gaps takes time that can't be compressed.

Starting preparation before you have a contract requirement is the move. The controls you implement for CMMC are also just good security practice — they protect your business from the ransomware attacks and supply chain intrusions that target DIB contractors regardless of contract status.

The Decision That Matters Most

Before you can make good decisions about CMMC implementation, you need to know your actual current state. Not what your IT staff thinks your security posture is. Not what a vendor told you about their product. An independent gap assessment that maps your current environment against all 110 Level 2 requirements and tells you where you actually stand.

That gap assessment — typically $5,000–$15,000 for a small contractor — is the starting point for everything else. It determines your remediation budget, your timeline, and whether you need to hire, outsource, or both.

For more on how to structure that initial assessment and prioritize the resulting remediation work, the CMMC gap assessment guide walks through the process. Or ask the assistant below — it can help you think through your current posture and what a realistic path to certification looks like. Organizations that invest in building real incident response capability recover faster and with less damage.