Hardening

Hardening is the process of strengthening a system, component, or structure to resist or withstand adverse conditions, events, or attacks. It is applied in fields such as information security, physical security, and engineering. The common goal is to reduce the attack surface, minimize vulnerabilities, and improve resilience against failures.

In information security, system hardening aims to reduce risk by removing unnecessary services, accounts, and features; applying patches and secure configurations; enforcing least privilege; and strengthening networks through segmentation, firewalls, and disabled unused ports. It also includes strong authentication, such as multi-factor authentication, secure logging, regular vulnerability assessments, backups, and formal change management.

Software and hardware hardening involves practices throughout the development and deployment lifecycle. This includes threat modeling, secure coding, code review, input validation, and avoiding insecure defaults. It favors defense in depth, minimal privileges for processes, memory safety where possible, integrity checks, signed updates, and the use of sandboxing, containers, or virtualization to limit exposure.

In physical security, hardening targets buildings and infrastructure. Measures include reinforced doors and windows, blast resistance where appropriate, tamper-resistant hardware, robust access controls, surveillance, intrusion detection, and environmental controls such as fire suppression and redundant power. Supply chain hardening and secure procurement practices are also part of physical hardening.

Hardening involves trade-offs among security, usability, performance, and maintenance. It requires ongoing assessment and updates as threats evolve and technologies change. Adherence to recognized standards and benchmarks, such as CIS, NIST, or IEC guidelines, can help organizations implement consistent controls.