CMMM Kill Chain

Posted by Guest Author - Tom Cornelius on Oct 25th 2020

The concept of creating a “CMMC Kill Chain” started off as a bit of a dare… kind of a “Here! Hold my coffee!” moment among a small group of CMMC practitioners to create a proof of concept for an efficient way to plan out a roadmap to successfully pass a CMMC assessment. The end result is a viable approach for anyone to use in order to create a prioritized project plan for CMMC pre-assessment activities.

Why “CMMC Kill Chain” you ask? As you very well may know, Lockheed Martin published a “Cyber Kill Chain” methodology that documents the phased approach malicious activities tend to follow. The concept is simply that it is easier to stop and prevent further damage if those malicious activities are discovered earlier, rather than later. When you look at CMMC's zero tolerance for deficiencies, if you have a single deficiency in a process or practice, you will fail your CMMC assessment. Given that reality with CMMC, the concept of the CMMC Kill Chain is that if you apply a prioritized, phased approach towards CMMC-related pre-assessment activities, it is possible to avoid rework and cascading failures by addressing dependencies earlier in the process. The bottom line is this model breaks down CMMC into 24 major steps, which can then be translated into a project plan. Pour a cup of coffee and enjoy!

This project was approached from the perspective of, “If I was hired at a company, what would my plan be to start from nothing to get a company to where it could pass an assessment?” All of the CMMC practices and processes are addressed within the CMMC Kill Chain, but it is clear that the prioritization and “bucketing” of practices into phases is a subjective endeavor and not everyone may agree with my approach. Just understand that every organization is different and you will invariably need to modify the approach to fit your specific needs.

Background on the Kill Chain Concept

The history of the kill chain has military origins, where a "kill chain" is a phase-based model that addresses the lifecycle of steps necessary to launch a successful attack against enemy forces. Conversely, it also is used defensively to understand and anticipate how enemies would likely launch an attack on friendly forces. Just search for "military kill chain" in a search engine if you want to learn more about that concept.

Applying The Kill Chain Model To CMMC

You might be asking yourself how a kill chain model applies to CMMC (side note - maybe you haven’t had enough coffee yet, so that could be the issue. It is possible. Seriously.). The root issue pertains to the situation facing many IT & cybersecurity professionals who are looking at 2021 with dread: These front-line IT/cybersecurity practitioners currently do not know where to start, let alone what path they need to follow to pass a CMMC assessment. There is a plethora of "What is CMMC?" guidance on LinkedIn, webinars and on the Internet in general, but there is a lack of practical guidance of HOW you are actually supposed to "do CMMC" in realistic terms. This is where the dare came in from a peer of mine to build a roadmap that would be usable for (1) anyone starting out or (2) anyone wanting to double check their approach. (note - for consultants who want to leverage the CMMC Kill Chain, by all means go for it - it is freely usable under Creative Commons licensing). This model will also be added to the CMMC Center of Awesomeness website if you are looking for it in the future. You can also download it by clicking on the image below to get a PDF version of the graphic and description. 

CMMC Kill Chain

CMMC Project Plan

The premise of the CMMC Kill Chain is to build a viable project plan from the perspective of a prioritized listing of tasks in order to successfully prepare for and pass a CMMC assessment. Errors or misguided adventures with people, processes and technology earlier in CMMC practice/process implementation activities will have cascading effects, so the CMMC Kill Chain is meant to provide a model for prioritizing CMMC-related pre-assessment activities.

CMMC Kill Chain Phases

Here is information on the 24 phases of the CMMC Kill Chain (these correspond to the pretty picture diagram):

  1. Define What CUI Is For Your Specific Business Case. This should be self-explanatory and is based on your contract(s).
  2. Establish The Scope of The CMMC Assessment Boundary. This has four subcomponent steps: (1) Create a Data Flow Diagram (DFD) that shows how CUI flows from the DoD all the way down to subcontractors; (2) Create a detailed asset inventory for all systems, applications and services for both in-scope and out-of-scope assets; (3) Create a detailed network diagram that includes where CUI is stored, transmitted and/or processed; and (4) Inventory Third-Party Service Providers (TSP) to determine TSP access to CUI and/or in-scope systems, applications and/or services.
  3. Document The Environment. This has two subcomponent steps: (1) Start populating the System Security Plan (SSP); and (2) Create a Plan of Action & Milestone (POA&M) to track and remediate deficiencies.
  4. Define The Network Architecture. This involves implementing a network architecture that ensures it is built on secure engineering principles and enclaves to protect sensitive information (e.g., FCI/CUI). POA&M deficiencies & document procedures.
  5. Plan, Identify Gaps & Prioritize Resources. This has six subcomponent steps: (1) Define applicable statutory, regulatory and contractual obligations (including DFARS, FAR, NIST 800-171 and CMMC); (2) Perform a gap assessment from applicable statutory, regulatory and contractual obligations; (3) Develop & implement policies and standards to address applicable statutory, regulatory and contractual obligations; (4) Identify the necessary People, Processes & Technology (PPT) that are necessary and appropriately sized; (5) Develop & implement a resource plan (e.g., business plan, budget, road map, etc.) to meet compliance obligations; and (6) Prioritize objectives from the resource plan for PPT requirements. POA&M any deficiencies from this phase.
  6. Develop Procedures. This has two subcomponent steps: (1) Develop & implement procedures to implement policies & standards; and (2) Define processes to securely handle CUI. POA&M any deficiencies from this phase.
  7. Risk Management. Develop & implement a Risk Management Program (RMP) to identify, assess and remediate risk. POA&M deficiencies & document procedures.
  8. Change Control. Develop & implement change control processes, including a Change Control Board (CCB). POA&M deficiencies & document procedures.
  9. Incident Response. Develop & implement incident response capabilities to detect, respond and recover from incidents. POA&M deficiencies & document procedures.
  10. Situational Awareness. Develop & implement situational awareness capabilities through log collection and analysis (e.g., SIEM). POA&M deficiencies & document procedures.
  11. System Hardening. Identify, build & implement secure baseline configurations (e.g., hardening standards) for all technology platforms. POA&M deficiencies & document procedures.
  12. Centralized Management. Build & implement Group Policy Objects (GPOs) for Microsoft Active Directory (AD). POA&M deficiencies & document procedures.
  13. Identity & Access Management. Develop & implement Identity & Access Management (IAM) to address "least privilege" and Role-Based Access Control (RBAC). POA&M deficiencies & document procedures.
  14. Maintenance. Develop & implement proactive maintenance practices. POA&M deficiencies & document procedures.
  15. Attack Surface Management / Vulnerability Management. Develop & implement Attack Surface Management (ASM) practices. POA&M deficiencies & document procedures.
  16. Asset Management. Develop & implement technology asset management practices. POA&M deficiencies & document procedures.
  17. Personnel Security. Work with Human Resources (HR) to ensure personnel security requirements are integrated into HR operations. POA&M deficiencies & document procedures.
  18. Network Security. Develop & implement network security practices. POA&M deficiencies & document procedures.
  19. Business Continuity. Develop & implement business continuity capabilities. POA&M deficiencies & document procedures.
  20. Cryptography. Develop & implement cryptographic key management and data encryption capabilities. POA&M deficiencies & document procedures.
  21. Physical Security. Develop & implement physical security practices. POA&M deficiencies & document procedures.
  22. Threat Intelligence. Develop & implement a threat intelligence capability. POA&M deficiencies & document procedures.
  23. Security Awareness Training. Build and maintain a security-minded workforce through training & awareness. POA&M deficiencies & document procedures.
  24. Internal Audit. Build and maintain an "internal audit" or Information Assurance (IA) capability to govern controls. POA&M deficiencies & document procedures.

Background On The Logic Used In This Model

Here is a quick explanation on some of the reasoning used for this model:

  • You can't legitimately assess changes, vulnerabilities, threats, etc. without first having a handle on risk management and a defined risk threshold. Risk management is the key building block that other practices rely upon.
  • Once you have solid risk management practices, change control is the second most important phase to address, since that is needed to legitimately alter other practices and you need to be able to document your changes and track open issues in a POA&M (e.g., evidence of due care).
  • From there, the assumption is that you will discover issues so incident response capability needs to exist (note - DFARS incident reporting requirements already apply if you currently store, process and/or transmit CUI as part of a DoD contract).
  • Event logging/SIEM is next and needs to exist before secure configurations, since logs need to get sent somewhere. You need to have this logging infrastructure in place before you get into secure configurations.
  • Secure configurations and centralized management (e.g., GPOs) almost go hand-in-hand, but before you can centrally manage configurations, they need to be defined and standardized.
  • Next, identity and access management needs to be locked down to ensure aspects of least privilege and RBAC are implemented. The reason IAM comes after secure configurations is due to troubleshooting - if you have "gold standard" secure builds to work from, it is easier to then assign permissions/RBAC that will work with those builds. The alternative is your new configs break your IAM/RBAC, which is bad. Avoid that.
  • You realistically can’t do vulnerability management without first having solid maintenance capabilities, so maintenance needs to be formalized with change control integrations. Maintenance needs to be tied into change management, which has a risk management component to it.
  • The concept of vulnerability management is broad and is best summed up by the term “attack surface management” where you are doing what you can to minimize the ways an adversary can attack. This relies on maintenance practices and change management being in place and operating.
  • From there, the remaining phases are relatively subjective - it really is. However, the “internal audit” function realistically needs to come last where control validation testing assesses how well controls are implemented. This can help serve as a pre-audit function.