Understanding NIST 800-53 Control Families and Medium-Impact Requirements

Introduction

NIST Special Publication 800-53 is a widely recognized security and privacy framework that provides organizations with a comprehensive set of security controls. These controls help federal agencies and businesses operating in regulated industries strengthen their cybersecurity posture. For companies hosting their infrastructure on AWS, aligning with NIST 800-53 Medium-Impact requirements ensures a robust security framework that mitigates risks while adhering to compliance mandates.

Overview of NIST 800-53 Control Families

NIST 800-53 defines 20 different control families, each covering a distinct area of cybersecurity. These families group related security and privacy controls, helping organizations categorize and implement security best practices. Below is a breakdown of these control families:

1. Access Control (AC): Managing access to systems and data through authentication and authorization mechanisms.
2. Awareness and Training (AT): Ensuring employees and stakeholders are educated on security policies and threats.
3. Audit and Accountability (AU): Implementing logging and monitoring capabilities to track security-related events.
4. Security Assessment and Authorization (CA): Establishing security assessments, risk management, and authorization processes.
5. Configuration Management (CM): Standardizing security settings and managing configurations across systems.
6. Contingency Planning (CP): Developing and testing business continuity and disaster recovery plans.
7. Identification and Authentication (IA): Enforcing user identity verification through strong authentication mechanisms.
8. Incident Response (IR): Defining and implementing strategies for responding to security incidents.
9. Maintenance (MA): Ensuring systems are updated and maintained securely.
10. Media Protection (MP): Protecting sensitive data stored in physical and digital media.
11. Personnel Security (PS): Managing background checks, security clearances, and user privileges.
12. Physical and Environmental Protection (PE): Securing physical infrastructure and monitoring environmental controls.
13. Planning (PL): Developing policies and security planning strategies.
14. Program Management (PM): Establishing an overarching security management program.
15. Risk Assessment (RA): Identifying and assessing risks to systems and data.
16. System and Services Acquisition (SA): Ensuring security is integrated into procurement and software development.
17. System and Communications Protection (SC): Securing network communications and system data.
18. System and Information Integrity (SI): Detecting and mitigating vulnerabilities and security threats.
19. Privacy Controls (PT): Protecting Personally Identifiable Information (PII) and ensuring privacy compliance.
20. Supply Chain Risk Management (SR): Addressing risks related to third-party vendors and supply chain dependencies.

Medium-Impact Baseline Requirements in AWS

For organizations operating in AWS under a moderate-risk profile, the Moderate Baseline of NIST 800-53 applies. Below are key medium-impact requirements and how AWS services can help meet them:

1. Access Control (AC) Implementation in AWS

Procedures:

• Define and enforce IAM policies for least privilege access.
• Implement Multi-Factor Authentication (MFA) for AWS accounts and key resources.
• Review and update access control policies regularly using AWS IAM Access Analyzer.
• Use AWS Organizations and Service Control Policies (SCPs) to restrict access at an organizational level.

2. Audit and Accountability (AU) in AWS

Procedures:

• Enable AWS CloudTrail for logging and monitor API activity.
• Configure Amazon CloudWatch Logs to capture real-time security events.
• Set up AWS Security Hub to consolidate security findings and compliance reports.
• Store and archive logs in Amazon S3 with appropriate lifecycle policies.

3. Configuration Management (CM) in AWS

Procedures:

• Use AWS Config to track and enforce compliance with configuration policies.
• Implement AWS Systems Manager Patch Manager to automate system updates and patching.
• Establish baseline AMIs with hardened security configurations.

4. Incident Response (IR) with AWS Tools

Procedures:

• Enable AWS GuardDuty for continuous threat detection and anomaly monitoring.
• Set up AWS Security Hub to centralize security incidents and streamline responses.
• Define and test automated response playbooks using AWS Lambda and AWS Step Functions.
• Conduct periodic security incident drills and tabletop exercises.

5. Risk Assessment (RA) & Security Assessment (CA)

Procedures:

• Use AWS Artifact for compliance documentation and risk analysis.
• Conduct regular security scans using AWS Inspector.
• Perform risk assessments leveraging AWS Trusted Advisor and AWS Well-Architected Tool.

6. System & Communications Protection (SC)

Procedures:

• Implement AWS KMS to manage and control encryption keys.
• Enforce encryption of data at rest using Amazon S3 Server-Side Encryption (SSE) and EBS encryption.
• Encrypt data in transit using TLS/SSL and AWS Certificate Manager.
• Deploy AWS WAF and AWS Shield to protect against web-based attacks.

7. System & Information Integrity (SI)

Procedures:

• Use Amazon Macie to discover and classify sensitive data.
• Deploy AWS Config rules to monitor system integrity and security compliance.
• Implement AWS Detective for analyzing and investigating security threats.
• Automate remediation of security findings using AWS Lambda functions.

Conclusion

Adhering to NIST 800-53 Medium-Impact requirements is crucial for organizations operating in AWS that need a structured and rigorous approach to security. By leveraging AWS security services, companies can effectively implement NIST control families, improve compliance, and enhance their overall security posture. Organizations should continuously assess their security framework and utilize AWS best practices to meet evolving compliance needs.