cbSecurity is a security module that provides authentication, authorization, and security services for ColdBox applications. It allows developers to validate user credentials, log users in and out, track security in sessions or custom storage, validate permissions and roles, and more. cbSecurity includes features like security firewalls, rules, handler annotations, and utilities to help secure events, URLs, and views based on roles and permissions. It also supports integrating with various authentication services and provides methods for authentication, authorization contexts, blocking access, securing views, and more.