Detection and Response to Incidents in the NIST Framework

Detection and response to security incidents is one of the most important functions of the NIST cybersecurity framework and of your role as a cybersecurity analyst within an organization. In this function, we focus on the early identification of suspicious or malicious activities in information systems, through the implementation of monitoring tools and technologies such as intrusion detection systems and log analysis.

An organization must address emerging and current issues by identifying new or revised policies, procedures, operations, and their risk factors. The NIST Framework developed several clauses to align with the needs of an organization.

• Monitoring and detection of security events.

The identification of events and the verification of the effectiveness of the measures taken are determined by the monitoring and detection of security events. Security event monitoring involves the constant supervision of information systems for suspicious or malicious activities. Ideally, effective monitoring is achieved through network monitoring strategies and a security infrastructure designed for anomaly detection, with tools such as firewalls, IDS, and IPS.

During monitoring, we look for any unauthorized connection, device, or software. We can also reinforce weaknesses through vulnerability scans.

The NIST framework recommends following a four-phase approach for monitoring and detecting security events: planning, implementation, evaluation, and improvement.

In the planning phase, organizations must define their monitoring and detection objectives, as well as establish clear policies and procedures. It is also important to identify critical assets and the security events to be monitored, and to establish criteria for alert generation.

The implementation phase involves selecting and implementing the appropriate monitoring tools and technologies. This may include configuring intrusion detection systems, implementing log analysis solutions, and setting up custom alerts. In addition, mechanisms must be established to securely collect and store security event data.

Once the monitoring system has been implemented, it is important to evaluate its effectiveness. This involves regularly reviewing logs and generated alerts, and conducting trend analysis to identify possible security gaps or areas for improvement. Penetration tests and incident simulations should also be conducted to assess the system's detection and response capabilities.

The improvement phase focuses on the continuous optimization of the security event monitoring and detection system. This may include updating the tools and technologies used, training staff in new attack techniques, and implementing additional controls to mitigate identified vulnerabilities.

• Log management and audit logs.

Log management refers to the process of collecting, storing, and analyzing information generated by information systems and security-related activities. Logs may include security events, access logs, configuration change logs, audit logs, among others. These logs are valuable for identifying security incidents, forensic investigation, and regulatory compliance.

Audit logs, in turn, are a subset of security logs and focus on tracking and recording audit activities performed on an information system. These logs provide traceability of actions carried out by auditors, such as security reviews, risk assessments, and penetration tests. In addition, audit logs allow for the monitoring and control of audit activities, as well as the review and analysis of the results obtained.

Within the NIST cybersecurity framework, a series of requirements and best practices are established for log management and audit logs. Some of these requirements include:

• Comprehensive log collection: Logs of all activities relevant to the security of information systems must be collected, including security events, configuration changes, and user actions.

• Secure storage: Logs must be stored securely to prevent alteration, loss, or unauthorized access. It is recommended to use encryption techniques and periodic backups.

• Proper retention: Logs must be retained for an appropriate period, in accordance with regulations and the organization's internal policies. This allows for the review and analysis of logs in case of incidents or audits.

• Privacy protection: It is important to ensure the protection of the privacy of the data contained in the logs. Anonymization and personal data protection measures must be applied, in accordance with current regulations.

• Incident response and data recovery.

Incident response is a set of actions and procedures carried out to detect, analyze, and respond to security incidents in an information system. These incidents may include cyberattacks, security breaches, malware, data theft, among others. The main objective of incident response is to minimize the impact of incidents and restore the normal operation of the information system as quickly as possible.

The NIST Framework establishes some best practices for effective incident response. Among these best practices are:

• Incident response plan: An incident response plan must be developed and maintained, establishing the roles and responsibilities of the response team members, the procedures to follow, and the tools to use during a security incident.
• Early detection systems: Intrusion detection and security monitoring systems must be implemented to quickly identify security incidents. This enables a faster and more effective response.
• Incident assessment and classification: Incidents must be assessed and classified according to their severity and impact on the information system. This helps prioritize response actions and allocate appropriate resources.
• Containment and mitigation: Measures must be taken to contain and mitigate the effects of security incidents. This may include isolating compromised systems, removing malware, and restoring critical services.
• Forensic investigation: In cases of serious incidents, a forensic investigation must be carried out to determine the origin and cause of the incident. This helps prevent future incidents and strengthen security measures.

Data recovery, in turn, refers to the process of restoring the integrity and availability of data after a security incident. This involves recovering backups, reconstructing damaged or lost data, and implementing measures to prevent future data loss.

Some best practices for data recovery within the NIST cybersecurity framework include:

• Regular backups: Periodic backups of critical data must be performed and stored in secure locations. This ensures that data can be restored in case of loss or damage.
• Recovery testing: Periodic data recovery tests must be performed to verify the effectiveness of procedures and backups. This helps identify potential problems and improve recovery processes.
• Backup security: Backups must be protected using encryption techniques and restricted access. This prevents unauthorized access to backup data.
• Documentation and updating: Clear and up-to-date documentation of data recovery procedures must be maintained. This facilitates a quick and effective response in case of incidents.

☝ Good management in the detection and response to cybersecurity incidents will make the difference in the success rate we could have in defending against an anomaly or threat within the organization. Our job as cybersecurity analysts is to ensure that all functions and tools for effective detection and incident response plans are in sync with the organization's needs.