Techniques for reducing the attack surface of an operating system.
System hardening is the process of securing a system by reducing its surface of vulnerability. A larger attack surface means more potential entry points for an attacker. Hardening involves applying a methodical approach to securing a system's configuration and settings to eliminate as many security risks as possible. The goal is to create a more resilient system that is more difficult to compromise. Hardening is not a one-time task but an ongoing process. The specific steps can vary depending on the operating system (Windows, Linux, macOS) and the system's role (web server, database server, workstation), but the principles are universal. Common hardening techniques include: 1. Removing or disabling unnecessary software and services. Every piece of software running on a system is a potential vulnerability. If a service isn't needed for the system's function, it should be removed. 2. Configuring user authentication policies. This involves enforcing strong password policies, setting account lockout thresholds after failed login attempts, and restricting administrator-level access. 3. Applying the Principle of Least Privilege. Users and services should run with the minimum permissions required to do their jobs. 4. Installing and configuring a host-based firewall. This allows you to control which network traffic is allowed to and from the machine. 5. Enabling logging and monitoring. Detailed logs provide an audit trail that is crucial for detecting and investigating security incidents. Many organizations use standardized hardening benchmarks, such as those from the Center for Internet Security (CIS), which provide detailed, step-by-step checklists for securing a wide range of operating systems and applications.