How to Develop a System Security Plan (SSP) for CMMC

EXECUTIVE BRIEF

Your organization's System Security Plan (SSP) is a key document for your security teams as well as your compliance journey. Here is what defense contractors need to know about them: 

• SSPs provide a clear and detailed picture of your security posture
• A required document for CMMC and NIST compliance
• It is a living document, make sure to keep updating it as you enhance your cybersecurity tools

Dig deeper and continue learning below!

The Cybersecurity Maturity Model Certification (CMMC) is a critical requirement for defense contractors seeking to protect sensitive government information. A foundational element of CMMC compliance is the System Security Plan (SSP). This document serves as a roadmap for implementing and maintaining the necessary security controls. This blog post will provide CXOs, VPs, and Directors within defense contracting businesses with a clear understanding of SSPs and their importance in achieving CMMC certification. 

What is a System Security Plan (SSP)?   

A System Security Plan (SSP) is a formal document that details how an organization will implement and maintain security controls to protect its information systems. It's the cornerstone of your CMMC compliance efforts, demonstrating your commitment to safeguarding Federal Contract Information (FCI) or Controlled Unclassified Information (CUI). 

Is an SSP Considered Controlled Unclassified Information (CUI)? 

While the SSP itself isn't necessarily CUI, it often contains information about CUI and the systems that process it.  Therefore, it should be treated with appropriate confidentiality and protection measures.  Understanding the relationship between SSPs and CUI is crucial for CMMC compliance. 

Why are SSPs Essential for Compliance? 

SSPs are essential because they provide a clear and documented picture of your organization's security posture. They are required to meet NIST 800-171 requirements, which are the basis for CMMC.  Without a detailed and up-to-date SSP, achieving CMMC certification is impossible. 

Understanding the Levels of CMMC and SSP Requirements 

CMMC 2.0 has three maturity levels, each with specific security requirements.  As your business progresses through the levels, so do the complexity and detail required in your SSP. 

• Level 1 (Foundational): Focuses on 17 basic cybersecurity practices selected from NIST 800-53. 

• Level 2 (Advanced): Introduces stringent cybersecurity practices, requiring adherence to all 110 controls and 320 objectives outlined in NIST SP 800-171. 

• Level 3 (Expert): Includes the same requirements as Level 2 and an additional 24 advanced security measures selected from NIST 800-172. 

How Do I Create a System Security Plan? 

A well-structured SSP should include the following core elements: 

• System Description: A clear overview of the system, its purpose, and its functionalities. 

• System Boundaries: Defining the scope of the system and what is included within its boundaries. 

• Security Controls: Detailed descriptions of the security controls implemented to protect the system and CUI. 

• Interconnections: Documentation of any connections between the system and other systems. 

• Incident Response Plans: Procedures for responding to and recovering from security incidents. 

Step-by-Step Guide to Creating an SSP   

• Conduct an Initial Risk Assessment: Identify potential threats and vulnerabilities to your systems. 

• Identify System Components and Boundaries: Define the scope of your system and its components. 

• Define Security Requirements and Controls: Select and implement the appropriate security controls based on your risk assessment and targeted CMMC level. 

• Document Procedures: Clearly document all procedures related to each security domain that addresses each control at the objective level. 

What Information Should Be Included in an SSP?   

Your SSP must include detailed information about your security controls, how they are implemented, and who is responsible for maintaining them.  It should be a living document that is regularly reviewed and updated. 

Best Practices for Implementing SSP in Compliance with CMMC 

• Maintaining an Up-to-Date SSP: Regularly update your SSP to reflect changes in your systems, threats, and regulatory requirements. 

• Defining Roles and Responsibilities: Clearly define who is responsible for maintaining and updating the SSP. 

• Aligning with CMMC Requirements: Ensure your SSP aligns with the specific requirements of your target CMMC level. 

Next Steps for Defense Contractors 

Your SSP is a critical component of your CMMC journey.  It demonstrates your commitment to protecting sensitive information and is essential for achieving certification. 

>> Contact ISI today for expert guidance to accelerate your compliance efforts and ensure a seamless certification process. 

FAQ 

What is a NIST 800-53 System Security Plan?   

NIST 800-53 is the basis for CMMC Level 1, the maturity level for defense contractors who only handle Federal Contract Information (FCI). If your business’ goal is to develop an SSP for CMMC Level 1, you will want to tailor it to these cybersecurity requirements.  

How is an SSP Different from a Security Policy?   

A security policy outlines high-level security objectives and principles. The SSP, on the other hand, details how those policies are implemented in a specific system. Think of the policy as the "what" and the SSP as the "how." 

What is a Plan of Action and Milestones (POA&M)?   

A POA&M is a document that identifies deficiencies in your compliance posturing and outlines time-bound remediation tasks to achieve full compliance. CMMC does allow for POA&Ms at Levels 2 and 3, however, only select controls are allowed on a POA&M for conditional certification.