Inheritance Isn’t Automatic Compliance
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One of the most persistent and costly misconceptions in Cybersecurity Maturity Model Certification readiness is the belief that when a Managed Service Provider or Managed Security Service Provider “handles security,” the contractor is automatically compliant.
Many Defense Industrial Base organizations struggle during assessments because they assume inherited controls equal compliance. Assessors require clear, mapped, and validated evidence for every inherited control. If you cannot demonstrate that control is implemented and effective in your environment, it will not pass.
As a CMMC Level 2 Certified MSSP and Registered Provider Organization, MAD Security consistently sees this misunderstanding during readiness efforts. This blog breaks down what inheritable controls are, how the shared responsibility model works, what assessors expect, and how you can best prepare.
What Are Inheritable Controls In The CMMC Framework
Inheritable controls are security requirements your organization relies on a third-party provider to implement. Even though the provider performs the technical function, the control is not automatically considered compliant unless you can demonstrate that it is properly implemented and applicable to your CUI environment.
Common examples include:
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Physical and environmental security in a FedRAMP-authorized cloud environment |
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Centralized logging and SIEM operations delivered through an MSSP or SOC |
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Patch management and infrastructure hardening maintained by a cloud platform |
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Email security and filtering delivered through a managed email solution |
These controls are considered “inherited” because the provider performs the implementation. However, you must still:
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Document the inheritance |
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Show its relevance to your environment |
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Provide evidence that it is effective |
Assumptions such as “our MSP handles that” are not enough assessors to expect proof.
Understanding The Shared Responsibility Model
In most environments, responsibilities are split between the contractor, the provider, or both. Misunderstanding this structure is a major source of compliance failures. Recognizing where each responsibility sits ensures you document each control accurately.
How Responsibilities Are Divided
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Control Area |
Contractor Responsibility |
Provider Responsibility |
Shared Responsibility |
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Data center physical security |
Not Responsible |
Fully Responsible |
Not Shared |
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Endpoint protection |
Device configuration & enforcement |
Tooling/management(if managed service) |
Joint monitoring |
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User access control policies |
Policy creation & enforcement |
Not Responsible |
Not Shared |
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Audit logging & monitoring |
Log review, alert triage |
Log collection, tooling |
Continuous monitoring |
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Incident response |
Internal coordination & reporting |
Detection & containment |
Joint incident handling |
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Multi-factor authentication (MFA) |
Enforcement, user lifecycle management |
MFA capability |
Combined configuration |
Even when a provider operates a technical function, you still retain responsibility for governance, oversight, configuration, and documentation. You can outsource security tasks, but not compliance accountability.
What Certified Third-Party Assessor Organizations Expect Regarding Inherited Controls
Assessors focus on whether each requirement is implemented and effective, including those inherited from providers. They evaluate what you can demonstrate, not what the provider claims to deliver.
Core Expectations for Inherited Controls
Assessors expect confirmation that:
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The control is implemented in your environment |
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The control is effective |
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Ownership and boundaries are clearly documented |
Documentation and Artifacts Assessors Will Review
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A System Security Plan marking inherited controls |
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A Customer Responsibility Matrix defining ownership |
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Provider-generated evidence such as SIEM logs, tickets, monitoring reports, or vulnerability scans |
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Contracts, SLAs, or attestation letters |
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Network diagrams and CUI boundary maps |
If this documentation is missing, the control will be marked “Not Met,” even if technically performed by the provider.
Required Documentation to Prove Inherited Controls
Successfully validating inherited controls requires a cohesive, well-organized documentation package. This is essential for demonstrating readiness during an assessment.
System Security Plan (SSP)
Your SSP must:
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Identify each practice |
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Mark inherited controls |
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Name the responsible provider |
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Link directly to supporting evidence |
Customer Responsibility Matrix (CRM)
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Responsibilities owned by the provider |
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Responsibilities owned by your organization |
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Shared components |
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Evidence sources |
Provider Attestation or SLA
Your documentation should clarify:
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Service scope |
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Provider security responsibilities |
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Relevant certifications |
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Retention and response practices |
Objective Evidence of Implementation
Examples include:
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Log exports |
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Alert histories |
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Access reviews |
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MFA configuration screenshots |
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Incident tickets |
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Vulnerability scans |
MAD Security helps clients collect and maintain these artifacts through integrated operations and compliance support within our Risk and Compliance Services.
Best Practices for Managing Inheritable Controls Proactively
Clear documentation and ongoing oversight are essential to avoid control failures linked to inheritance. These practices strengthen audit readiness and streamline compliance.
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Engage Providers Early in the ProcessRequest CRMs, attestations, and evidence early to avoid delays. |
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Explicitly Document Inherited Controls in Your SSP
Ensure every inherited control is mapped and supported. |
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Maintain a Living CRMKeep your CRM current whenever systems, providers, or environments change. |
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Validate Regularly, Not Just OncePeriodic reviews ensure inherited controls remain effective and well documented. |
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Use a Virtual Compliance Management ApproachPrograms like our Virtual Compliance Management provide continuous structure for tracking inherited controls. |
How MAD Security Helps You Validate Inherited Controls for CMMC
MAD Security is a CMMC Level 2 Certified MSSP and Registered Provider Organization supporting contractors, assessment organizations, and complex environments navigating DFARS and NIST SP 800-171.
Our SOC and compliance teams deliver:
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24/7 monitoring, detection, and response |
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Evidence collection aligned with CMMC |
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SSP, CRM, POA&M, and policy development |
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Gap assessments and remediation guidance |
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Assessment preparation and support |
Key offerings include our Managed Security Services and our role as a CMMC RPO.
Compliance Depends on Evidence, Not Assumptions
Inheriting controls from a provider is common, but assuming they are automatically compliant is a critical mistake. Achieving CMMC Level 2 requires:
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Understanding shared responsibility |
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Documenting inherited controls clearly |
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Maintaining a complete SSP and CRM |
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Retaining objective evidence |
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Being prepared to demonstrate and defend your controls |
MAD Security provides both the operational security and the compliance expertise needed to help you confidently validate and maintain inherited controls.
Frequently Asked Questions (FAQs)
Original Publish Date: December 9, 2025
By: MAD Security
