EXECUTIVE BRIEF
Understanding NIST 800-171 is essential for defense contractors to secure sensitive information, maintain competitiveness and secure government contracts. This article details how:
- NIST 800-171 is a critical cybersecurity standard for defense contractors. It outlines 14 control families that cover a wide range of security measures, from access control and awareness training to physical protection and risk assessment.
- Compliance with NIST 800-171 is essential for defense contractors seeking CMMC certification. It helps ensure the protection of Controlled Unclassified Information (CUI) and can provide a competitive advantage in the defense industry.
Learn more and continue reading below!
For defense contractors looking to compete in an increasingly competitive marketplace, understanding the security controls laid out in the National Institute of Standards and Technology’s Special Publication 800-171 is essential. This blog thoroughly explains NIST 800-171’s 14 control families and explores compliance challenges, best practices, and future trends.
What Is NIST 800-171?
NIST 800-171 is a set of guidelines from the National Institute of Standards and Technology (NIST) that establishes recommended security requirements for protecting Controlled Unclassified Information (CUI). The guidelines apply to any non-federal systems and organizations that process, store, or transmit CUI, including any Department of Defense (DoD) contractor with a DFARS clause 252.204-7012 in their contract.
NIST’s Special Publication 800-171 was first published in June 2015 to strengthen cybersecurity at every step of the supply chain in both the public and private sectors. Since then, it has received regular updates and revisions, the most recent being Revision 3 in May 2024. While Revision 3 is the latest update, CMMC Level 2 requires defense contractors to implement the guidelines in Revision 2 to align with other DoD cybersecurity regulations.
What does NIST 800-171 Rev2 outline?
- NIST SP 800-171 outlines 110 security controls across 14 control groups or “families.”
- Within these controls, there are 320 objectives that you must meet to reach compliance.
NIST 800-171 was accompanied by a companion publication, NIST 800-171A, which provides procedures for organizations to self-assess their internal protocols for meeting these guidelines. NIST 800-171’s requirements and their corresponding assessment methods form the foundation for the Cybersecurity Maturity Model Certification (CMMC).
Why Is NIST 800-171 Important for Defense Contractors?
Understanding and enacting NIST 800-171 requirements is essential for contractors and subcontractors working within the Defense Industrial Base (DIB). Defense contractors that are seeking CMMC Level 2 or higher certification have to demonstrate that they have met and can remain in compliance with the 110 security controls set out in NIST 800-171 Rev2. These include controls and procedures that govern everything from physical security at your site to computer system configurations to employee training programs.
With the final CMMC Rule going into effect on December 16, 2024, defense contractors must be budgeting and planning for CMMC-related activities in 2025. Early preparedness positions your business at a strategic advantage for acquiring new contracts: CMMC requirements are expected to appear in new and updated contracts by Q2 of 2025, and businesses that have achieved compliance or are well along the path to doing so will have a significant leg up in the marketplace.
Understanding the 14 Families of NIST 800-171 Controls
But what are the 14 families of controls that make up NIST 800-171’s guidelines? Let’s take an in-depth look at each one.
1. Access Control (AC)
The largest of the 14 control families, Access Control (AC), governs how users and systems gain access to sensitive information at your company. They establish the framework for managing who can access what, when, and under what conditions.
They verify users' identities, regulate their permissions, and ensure that access to data aligns with organizational policies. They also monitor how information flows in and out of the system to prevent unauthorized disclosure or misuse.
The Access Controls required by NIST 800-171 include a range of technical and administrative measures designed to manage permissions and access points, such as:
- Multi-Factor Authentication (MFA): This requires users to verify their identity with two or more methods, such as a password and a one-time code sent to their mobile device.
- Role-Based Access Control (RBAC): This limits user access based on their role within the organization. For example, an administrator may have broader access than a general employee, who can only view specific CUI.
- Session Timeouts: These automatically log out users after a period of inactivity to prevent unauthorized access if a workstation is left unattended.
- Encryption for Remote Access: This protects data transmitted during remote access sessions using encryption protocols to secure communications.
- Wireless Access Control: This restricts access to internal networks via Wi-Fi using strong encryption (e.g., WPA3) and authentication methods.
- Monitoring and Auditing Access: This tracks and logs user activities, allowing security teams to detect unauthorized access attempts or anomalies in real-time.
2. Awareness and Training (AT)
Awareness and Training (AT) controls are designed to educate employees about their role in protecting CUI. These controls focus on raising awareness of potential threats and providing the knowledge needed to follow security policies effectively.
Specific implementations include regular employee security training sessions, phishing simulations to improve user vigilance, and role-specific training for individuals handling sensitive data. Organizations may also reinforce awareness training through ongoing initiatives like posters, newsletters, and periodic refresher courses to prioritize security throughout the workforce.
3. Audit and Accountability (AU)
Audit and Accountability (AU) controls help organizations track and monitor activities within their information systems to identify suspicious behavior or instances of unauthorized access. Every user action—such as logging in, accessing sensitive data, or making system changes—should be recorded and traceable. The goal is to maintain a clear record of events so that security teams can investigate incidents, detect anomalies, and hold people accountable.
Some of the key Audit and Accountability controls in NIST 800-171 include:
- Log Management: This involves keeping detailed logs of system activities, such as login attempts, data access, and changes to system configurations, which you can review later.
- Automated Alerts: This involves configuring systems to generate alerts for abnormal behavior that might indicate a security threat, such as repeated failed login attempts.
- User Activity Monitoring: This involves tracking and reviewing the actions of users with privileged access to ensure they aren’t misusing their permissions.
- Audit Trails: This involves creating tamper-proof records of key actions for later review, ensuring that any unauthorized or suspicious activities can be traced back to their source.
- Regular Audit Reviews: This involves performing periodic reviews of system logs and audit trails to ensure compliance with security policies and identify gaps or areas needing improvement.
4. Configuration Management (CM)
The goal of NIST 800-171’s Configuration Management (CM) controls is to maintain the integrity and security of your company’s systems by controlling how hardware, software, and network settings are set up and updated over time. This involves setting baseline configurations that define the secure state of a system, such as specifying which services should be enabled or disabled and which security patches should be applied. Changes to these configurations are tracked through a formal change management process, which includes reviewing and approving any modifications before they’re made.
Organizations must routinely scan their systems to detect unauthorized changes or vulnerabilities and use specific tools to enforce security settings, ensuring that configurations remain aligned with the company’s overall security policies. Any user-installed software must be controlled and monitored to prevent unapproved or malicious applications from compromising the system security plan (SSP).
5. Identification and Authentication (IA)
Identification and Authentication (IA) controls are designed to verify that users and devices attempting to access a system are who they claim to be. “Identification” means assigning a unique identity to each user or device; “authentication” means confirming that identity through various methods such as passwords, biometrics, or multi-factor authentication.
While similar to the Access Controls (AC) mentioned earlier, IA controls serve a distinct purpose. AC ensures users are only allowed to do certain things within a system, while IA ensures that the users accessing the system are indeed who they claim to be. To put it another way, AC ensures that John can only access the files his role permits; IA confirms that John is, in fact, the person logging in to John’s account.
6. Incident Response (IR)
When a cyberattack or a data breach occurs, Incident Response (IR) controls are designed to help organizations detect, respond to, and recover from it. These controls lay out a structured approach to identifying incidents, containing the threat, and mitigating any damage that may have been caused. Key components include developing and testing an incident response plan, establishing communication protocols for reporting incidents, and conducting post-incident analyses to prevent future occurrences.
7. Maintenance (MA)
Maintenance (MA) controls ensure that systems are regularly and securely serviced. These controls focus on activities like system updates, hardware repairs, and patch applications while ensuring that only authorized personnel perform maintenance. Key practices include monitoring and logging maintenance tasks, securing maintenance tools, and using controlled access for remote maintenance. The goal is to maintain the operational health of systems while preventing unauthorized access or disruptions during the process.
8. Media Protection (MP)
Media Protection (MP) controls are designed to safeguard sensitive information stored on physical and digital media, such as hard drives, USB devices, or printed documents. The aim is to manage the storage, access, transportation, and disposal of any media containing CUI.
Critical practices include encrypting data on portable devices and external drives, establishing procedures to track and monitor the movement of media, and securely sanitizing or destroying media that are no longer needed by wiping hard drives, degaussing magnetic media, or shredding physical documents to prevent any possibility of data recovery.
9. Personnel Security (PS)
Personnel Security (PS) controls are designed to make sure individuals who can access CUI and other sensitive information or systems are trustworthy and properly vetted. These include background checks, verifying clearances, and ensuring that personnel handling sensitive data meet security requirements. Personnel Security also includes procedures for revoking access when employees change roles or leave the organization. This prevents former employees or unauthorized individuals from retaining access to critical systems.
10. Physical Protection (PE)
True to its name, this family of controls safeguards the physical locations where sensitive information is stored or processed. Physical Protection (PE) prevents unauthorized individuals from accessing systems and equipment through traditional security measures like locked doors, visitor logs, badge systems, security personnel, surveillance cameras, and biometric authentication. Physical protection controls also safeguard equipment and media from environmental hazards, such as fire, flooding, or power surges, by using fire suppression systems or climate control measures.
11. Risk Assessment (RA)
Risk Assessment (RA) controls involve regularly evaluating potential threats and vulnerabilities and prioritizing which to address based on their likelihood and severity. Conducting vulnerability scans and penetration tests to identify weaknesses is a key feature of this family of controls, as is continuous monitoring for new threats. Organizations develop risk mitigation strategies to reduce their likelihood or impact as threats are identified.
12. Security Assessment (CA)
Unlike Risk Assessment, which focuses on assessors identifying and prioritizing potential risks, Security Assessment (CA) controls focus on evaluating and verifying the effectiveness of an organization’s current security measures.
This involves conducting regular tests and reviews of security policies, processes, and technologies to identify gaps or weaknesses in the system. The goal is to ensure all current controls function as intended and comply with relevant standards and regulations. Afterward, a plan of action is drawn up to address any identified deficiencies.
13. System and Communications Protection (SC)
Systems and Communication Protection (SC) controls maintain the confidentiality and integrity of data as it moves through systems, whether during routine communications or while being stored at rest. They protect system boundaries properly, preventing malicious actors from exploiting vulnerabilities to access sensitive information.
Required protections include:
- Encryption of Data at Rest and in Transit: Encrypting data, whether stored or as it moves across networks, ensures that unauthorized users cannot intercept and read sensitive information.
- Boundary Protection: This involves firewalls and gateways to monitor and control incoming and outgoing network traffic, preventing unauthorized access to internal systems.
- Session Locking: This automatically locks user sessions after periods of inactivity to prevent unauthorized access to unattended workstations.
- Separation of User and System Functions: This involves implementing mechanisms that separate user tasks and administrative functions to reduce the risk of privilege misuse.
- Monitoring and Protecting External Communications: This involves securing external data transmissions using technologies like VPNs and ensuring that remote system access is encrypted and controlled.
14. System and Information Integrity (SI)
Mechanisms that monitor systems for malicious activity and prevent unauthorized modifications are crucial to the System and Information Integrity (SI) control family. SI controls include anti-malware protections, intrusion detection systems, and automated alerts to identify and address potential security incidents. By detecting these issues early, these controls prevent data corruption and the spread of malware and ensure that any detected issues are swiftly reported to relevant personnel for an appropriate response.
NIST 800-171 Compliance Challenges Faced by Defense Contractors
With all these requirements to meet, it’s no wonder that achieving compliance can feel like a serious challenge for DoD government contractors. That’s especially true for small- to mid-sized organizations with limited resources, and the burden of implementing new procedures and introducing new technology will fall on employees who are already stretched thin with their current duties.
Meeting CMMC Requirements and Balancing Security with Operational Needs
Many small- to mid-sized businesses rightfully worry about how they can meet all these requirements efficiently, cost-effectively, and without disrupting or distracting themselves from their core business. Not every company has the resources and the internal expertise in cybersecurity frameworks or regulatory compliance to keep up with the regulations.
Screening Employees Before Granting Access to CUI
DoD contractors should follow a structured, multi-layered screening process to ensure that employees with access to CUI are trustworthy and qualified. A Facility Security Officer (FSO), working in conjunction with HR, can qualify employees by verifying citizenship, conducting thorough background checks and credit checks, and screening for insider risks through behavioral assessments and questionnaires.
Best Practices for Implementing and Maintaining NIST 800-171 Controls
Here are some best practices for implementing and maintaining NIST 800-171 controls.
- Adopt a phased compliance approach: Break the problem down into bite-size pieces. Start by conducting a gap analysis to understand which NIST 800-171 controls the organization currently meets and where it falls short. By focusing first on foundational security controls and addressing advanced requirements over time, you can spread out costs, minimize disruption, and steadily build toward compliance.
- Invest in automation and security tools: Automated tools for tasks like access control, log management, and vulnerability scanning reduce manual overhead and provide real-time alerts to keep security in check without impacting operations. Consider integrated solutions that provide a suite of services, such as incident response, data protection, and compliance tracking, to simplify management.
- Strengthen internal policies and training: Develop and communicate clear internal policies that align with NIST 800-171 controls to make compliance easier to follow and enforce across the organization. Employees are often the first line of defense in cybersecurity. Training them in best practices, data handling, and compliance requirements helps reduce risks from internal threats and mistakes, keeping compliance on track with minimal disruptions to operations.
- Leverage managed service providers (MSPs) and external expertise: Partnering with an MSP that specializes in CMMC compliance, like ISI, can bring necessary expertise without the cost of in-house staff. These providers can offer tailored solutions to make compliance more manageable and cost-effective.
Looking Ahead: Future Trends in NIST 800-171
Cyber threats are constantly evolving, and so is the regulatory landscape. The latest revision to NIST 800-171, Revision 3, streamlines the number of security controls while simultaneously expanding the number of discrete objectives that need to be met. Viewed in conjunction with changes from CMMC 2.0, the revision suggests a movement toward more organization-defined parameters, allowing greater flexibility for DoD contractors to define the specific benchmarks they need to meet.
At the same time, continuous monitoring through vulnerability scans, penetration testing, and other regular security assessments will become increasingly critical as DoD contractors affirm their compliance status annually.
Navigate NIST 800-171 Controls with ISI
Finding a trustworthy partner to help you keep up with these changes can be a game-changer. As a leading Registered Provider Organization with 3 RPs on staff and a track record of over 180 completed NIST assessments, ISI excels in guiding companies to achieve compliance with CMMC Level 2.
We offer scalable, customized personnel, IT, and facilities security solutions – resources that make us a one-stop shop for organizations looking to streamline compliance without relying on multiple vendors. Our advanced proprietary tools help DoD contractors through alerts, automation, and workflows that make compliance easier and more manageable, and our responsive 24/7 US-based customer service team understands DoD-specific challenges.
Schedule a discovery call to learn how we can help you meet your NIST 800-171 and CMMC compliance goals efficiently and cost-effectively.
FAQs about NIST 800-171 Controls
What Are NIST 800-171 Controls?
The “controls” in NIST 800-171A Rev2 are specific security requirements established by the federal government to ensure that sensitive data (particularly CUI) is properly safeguarded against cyber threats and other security risks. NIST 800-171 outlines 110 of these controls across 14 families (listed and detailed above).
How Many Domains Are There in NIST 800-171?
In this context, “domain” is just another word for “family,” so there are 14 domains. Those 14 domains are Access Control, Awareness and Training, Audit and Accountability, Configuration Management, Identification and Authentication, Incident Response, Maintenance, Media Protection, Personnel Security, Physical Protection, Risk Assessment, Security Assessment, System and Communications Protection, and System and Information Integrity.
What’s the Difference Between NIST 800-53 and 800-171?
NIST 800-53 is a comprehensive set of security and privacy controls to protect federal information systems, especially those handling classified data or operating in high-security environments. It covers various security requirements and offers a broad framework that federal agencies can tailor based on specific risk levels.
NIST 800-171, on the other hand, is narrower in focus and explicitly designed for non-federal organizations, particularly contractors, to protect CUI in their systems. It distills relevant controls from NIST 800-53 into a simpler set to secure CUI without the full complexity required for federal systems.
What’s the Difference Between ISO 27001 and NIST 800-171?
NIST 800-171 is a U.S.-specific standard for safeguarding CUI that applies to non-federal organizations working with the U.S. government. ISO 27001 is a broader, more flexible global standard for establishing, implementing, and maintaining an Information Security Management System (ISMS). NIST 800-171 is more prescriptive with its controls and limited in its application, whereas ISO 27001 is a global standard focused on risk management and continuous improvement across industries.
