3.11.2e

Threat hunting is an active means of defense that contrasts with traditional protection measures, such as firewalls, intrusion detection and prevention systems, quarantining malicious code in sandboxes, and Security Information and Event Management (SIEM) technologies and systems. Cyber threat hunting involves proactively searching organizational systems, networks, and infrastructure for advanced threats. The objective is to track and disrupt cyber adversaries as early as possible in the attack sequence and to measurably improve the speed and accuracy of organizational responses. Indicators of compromise are forensic artifacts from intrusions that are identified on organizational systems at the host or network level and can include unusual network traffic, unusual file changes, and the presence of malicious code. Threat hunting teams use existing threat intelligence and may create new threat information, which may be shared with peer organizations, Information Sharing and Analysis Organizations (ISAO), Information Sharing and Analysis Centers (ISAC), and relevant government departments and agencies. Threat indicators, signatures, tactics, techniques, procedures, and other indicators of compromise may be available via government and non-government cooperatives, including Forum of Incident Response and Security Teams, United States Computer Emergency Response Team, Defense Industrial Base Cybersecurity Information Sharing Program, and CERT Coordination Center. [SP 800-30] provides guidance on threat and risk assessments, risk analyses, and risk modeling. [SP 800-160-2] provides guidance on systems security engineering and cyber resiliency. [SP 800-150] provides guidance on cyber threat information sharing.