Detection of Screen Capture

Real-time monitoring identifies Hypertext Transfer Protocol (HTTP) requests to an embedded Human-Machine Interface (HMI) panel's built-in web server capturing screen images, or Virtual Network Computing (VNC) connections to embedded HMI panels, from source Internet Protocol (IP) addresses not in the approved operator workstation list. OT operational-fidelity gate: Do not alert on novelty, scan/read volume, or enumeration alone. Alert when the source role is not authorized for discovery/polling and the target scope, address/tag range, protocol, or rate deviates from the established operational baseline. Suppress normal SCADA/HMI/historian polling, commissioning, asset inventory, backup, diagnostics, and approved engineering activity.

Real-time monitoring identifies a process invoking screen capture Application Programming Interfaces (APIs) targeting an Human-Machine Interface (HMI) or operator workstation window, where the calling process is not a recognized Industrial Control System (ICS) vendor application or approved remote support tool, immediately followed by an image file write. OT operational-fidelity gate: Do not alert on novelty, scan/read volume, or enumeration alone. Alert when the source role is not authorized for discovery/polling and the target scope, address/tag range, protocol, or rate deviates from the established operational baseline. Suppress normal SCADA/HMI/historian polling, commissioning, asset inventory, backup, diagnostics, and approved engineering activity.