SCADA Security
SCADA security focuses on protecting Supervisory Control and Data Acquisition systems — the networked architectures that provide centralised monitoring and control over geographically dispersed industrial processes such as pipelines, power distribution, and water treatment facilities.
SCADA systems are a subset of Industrial Control Systems specifically designed to manage processes distributed across large geographic areas. A typical SCADA architecture consists of a central control server or master station, communication infrastructure (often including radio, cellular, or satellite links), Remote Terminal Units (RTUs) or PLCs at field sites, and Human-Machine Interfaces (HMIs) for operator interaction. They are the backbone of critical infrastructure including oil and gas pipelines, electrical grids, railway systems, and municipal water networks.
SCADA security faces unique challenges that distinguish it from conventional IT security. Many SCADA systems were deployed decades ago and run on legacy operating systems that can no longer be patched. The communication protocols commonly used — Modbus RTU, DNP3, and IEC 60870-5-104 — lack built-in authentication and encryption. Uptime requirements often approach 99.999%, making maintenance windows for security updates extremely difficult to schedule. Additionally, remote field sites may have limited physical security, exposing RTUs and communication equipment to tampering.
Attackers targeting SCADA systems may seek to disrupt operations, cause physical damage, hold infrastructure for ransom, or conduct espionage. Attack vectors include compromising the corporate network and pivoting into the SCADA environment, exploiting vulnerable remote access connections used by vendors and engineers, intercepting unencrypted SCADA protocols, and directly targeting internet-exposed HMIs or historians — a disturbingly common finding on platforms like Shodan.
Defending SCADA systems requires strict network segmentation, encrypted VPN tunnels for all remote access, whitelisting of authorised applications and communications, continuous monitoring with OT-aware security tools, and regular tabletop exercises that simulate cyber-physical attack scenarios.