System and Information Integrity

The System and Information Integrity family in NIST 800-171 Rev 2 focuses on ensuring that an organization’s information systems can detect, respond to, and correct issues that may compromise the integrity and security of Controlled Unclassified Information (CUI). This family emphasizes the importance of monitoring systems for vulnerabilities, applying security patches promptly, and ensuring that malicious software and unauthorized system changes are detected and addressed.

Key System and Information Integrity Requirements in NIST 800-171 Rev 2:

The System and Information Integrity family contains seven security requirements designed to help organizations protect their information systems from vulnerabilities, malware, and unauthorized modifications while ensuring the integrity of CUI.

1. Identify, Report, and Correct Information System Flaws (3.14.1)

Basic Requirement: Organizations must identify, report, and correct flaws in information systems in a timely manner.

Key Focus:

Regularly scan systems for security vulnerabilities and flaws.

Develop a process for reporting and addressing identified flaws, such as missing patches, software bugs, or misconfigurations.

Apply patches and updates promptly to reduce exposure to known vulnerabilities.

Example: Using vulnerability scanning tools to identify outdated software or missing patches and applying security updates within a defined timeframe.

2. Provide Protection from Malicious Code (3.14.2)

Basic Requirement: Organizations must protect their information systems from malicious code (e.g., viruses, malware, ransomware) by implementing appropriate defensive measures.

Key Focus:

Deploy and maintain antivirus software, anti-malware tools, and other technologies to detect, prevent, and mitigate malicious code.

Ensure that these tools are updated regularly to detect the latest threats.

Example: Installing and regularly updating antivirus software across all endpoints and scanning incoming files, emails, and web downloads for malware.

3. Monitor System Security Alerts and Take Action (3.14.3)

Basic Requirement: Organizations must monitor security alerts, advisories, and directives from various sources (e.g., security vendors, threat intelligence feeds) and take action to protect their systems.

Key Focus:

Regularly review alerts and advisories from sources such as software vendors, the Cybersecurity and Infrastructure Security Agency (CISA), or other trusted organizations.

Implement corrective actions based on the severity and relevance of the alerts to ensure system security.

Example: Subscribing to a threat intelligence feed and applying critical security patches when new vulnerabilities are discovered in widely used software.

4. Update Malicious Code Protection Mechanisms (3.14.4)

Derived Requirement: Organizations must regularly update mechanisms that protect against malicious code (e.g., antivirus software, firewalls) to ensure they remain effective against evolving threats.

Key Focus:

Ensure that all anti-malware tools are configured to automatically update virus definitions and security signatures to stay protected against the latest malware threats.

Example: Configuring antivirus software to receive automatic updates from the vendor to ensure it detects new malware strains.

5. Perform Periodic System Scans for Vulnerabilities (3.14.5)

Derived Requirement: Organizations must regularly perform vulnerability scans of their information systems to identify potential weaknesses or security gaps.

Key Focus:

Schedule regular scans (e.g., monthly or quarterly) using vulnerability scanning tools to identify unpatched software, misconfigurations, or other system vulnerabilities.

Ensure that scan results are reviewed and corrective actions are taken to address identified issues.

Example: Running a network-wide vulnerability scan every month to detect and fix missing security patches or open ports that could be exploited by attackers.

6. Perform Real-Time Monitoring of System and Network Activities (3.14.6)

Derived Requirement: Organizations must implement mechanisms to monitor system and network activities in real time to detect and respond to security events and anomalies.

Key Focus:

Use real-time monitoring tools, such as intrusion detection systems (IDS), security information and event management (SIEM) systems, and network traffic monitoring tools, to detect unusual activities and potential security breaches.

Example: Using a SIEM system to analyze logs and network traffic in real time and generate alerts if suspicious activities are detected.

7. Identify Unauthorized Use of Information Systems (3.14.7)

Derived Requirement: Organizations must implement measures to identify the unauthorized use of information systems and respond accordingly.

Key Focus:

Monitor systems for any unauthorized access attempts, privilege escalations, or the use of accounts that do not have the proper permissions.

Take corrective action when unauthorized activities are detected, such as disabling compromised accounts or blocking malicious IP addresses.

Example: Implementing user behavior analytics (UBA) to detect unusual login patterns that might indicate unauthorized access, such as repeated login attempts from unusual geographic locations.

Importance of System and Information Integrity in Cybersecurity:

Prevents Security Incidents: Regularly scanning for vulnerabilities, applying patches, and monitoring system activity helps prevent security incidents like data breaches, malware infections, and unauthorized access to CUI.

Protects Against Malicious Software: Implementing and maintaining up-to-date malware protection mechanisms such as antivirus software and intrusion detection systems helps prevent the spread of malicious code that could compromise sensitive data.

Ensures System Reliability: Maintaining the integrity of information systems ensures they function as intended without being compromised by flaws or unauthorized modifications. This helps prevent system downtime and ensures CUI remains secure.

Enables Timely Detection of Threats: Continuous monitoring of systems and real-time analysis of security alerts allows organizations to detect and respond to security threats before they can cause significant damage.

Supports Compliance: Organizations must ensure the integrity of their systems to comply with NIST 800-171 and other regulations governing the protection of CUI. Failing to address system vulnerabilities or allowing malware infections to occur could result in regulatory penalties.

Best Practices for System and Information Integrity:

Automate Vulnerability Scanning and Patching: Use automated tools to scan for vulnerabilities and apply security patches as soon as they are released. Schedule scans at regular intervals to ensure your systems are always up to date.

Use Real-Time Monitoring Tools: Implement SIEM systems, IDS/IPS, and other monitoring tools that provide real-time visibility into system and network activity, allowing you to quickly detect and respond to suspicious behavior.

Deploy and Update Antivirus and Anti-Malware Software: Ensure that all endpoints and servers are protected by up-to-date antivirus and anti-malware software that automatically receives the latest virus definitions and updates.

Implement Threat Intelligence Feeds: Subscribe to threat intelligence feeds and stay informed about the latest security advisories and directives from trusted sources like CISA, NIST, or software vendors.

Train Employees on System Security: Educate employees about the importance of system integrity, how to recognize potential security threats (e.g., phishing emails or malware infections), and how to report suspicious activities.

Respond Quickly to Alerts: When security alerts are received from monitoring systems or threat intelligence sources, take immediate action to investigate and mitigate any identified risks.

Review and Remediate Vulnerability Scan Results: After performing vulnerability scans, review the results carefully and implement corrective actions for any identified issues, such as applying patches or adjusting system configurations.

Summary:

The System and Information Integrity family in NIST 800-171 Rev 2 emphasizes the importance of maintaining the security, integrity, and functionality of an organization’s information systems. By regularly scanning for vulnerabilities, applying security patches, protecting against malicious code, and monitoring system activities, organizations can ensure that Controlled Unclassified Information (CUI) remains protected from security threats. Implementing these controls helps prevent security incidents, ensures compliance with regulatory requirements, and supports the overall integrity and reliability of information systems.