Definition
STIX, or Structured Threat Information Expression, is a standardized language and serialization format used to represent cyber threat intelligence. It provides a common framework for describing threat actors, campaigns, indicators of compromise, and courses of action in a machine-readable way. In practice, STIX enables the automated sharing and consumption of threat data between different security tools and organizations. This is crucial for improving threat detection, response, and overall security posture by allowing for quicker dissemination of actionable intelligence. For example, STIX can describe a specific phishing campaign, including the tactics used, the targeted industries, and the indicators associated with the malware. It is distinct from STTP (Structured Threat Information Transfer Protocol) which is a protocol for exchanging STIX data. You will encounter STIX in cybersecurity certifications like Security+, CySA+, and CISSP.