What Is OSINT?

**Executive Summary:** This report provides a concise primer on open-source intelligence (OSINT) and operational security (OPSEC), describing how publicly available information is collected, how attackers leverage OSINT across the cyber kill chain (from target selection and reconnaissance to delivery, exploitation, installation, C2, and actions on objectives), common misuse scenarios (e.g., spear phishing, social engineering, reconnaissance for malware delivery), and practical mitigations for employees and organizations including privacy hygiene, strong unique passwords, multi-factor authentication, patching, and email security controls.