Detections

Real-time monitoring identifies a mount event for removable storage media on an Industrial Control System (ICS) Linux asset, followed by execution of a binary from the mounted path within a short window. OT operational-fidelity gate: Alert only when the account/device/session violates the approved identity + source host/jump path/zone policy and is corroborated by access to a protected OT asset, execution, configuration change, or another security-relevant follow-on event. Suppress approved shift activity, vendor support, break-glass use, commissioning, and documented remote-access windows.

Real-time monitoring identifies a scripting interpreter process iterating through Industrial Control System (ICS) data sources and writing output to a local file or piping to a network socket, by a User Identifier (UID) not associated with documented automation scripts. 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 an Industrial Control System (ICS) Linux service process initiating an outbound connection on a commonly-used port to a destination not in the approved vendor domain list. OT operational-fidelity gate: Alert only when the asset's documented role does not permit the connection and the destination/proxy/service is outside the approved communications profile, with process/service identity used as corroboration where available. Suppress approved vendor support, update repositories, remote operations, failover paths, and documented temporary connectivity.

Real-time monitoring identifies an Industrial Control System (ICS) Linux service process making write Application Programming Interface (API) calls to field device Input/Output (I/O) at a rate exceeding the configured scan rate, from a User Identifier (UID) associated with the Supervisory Control and Data Acquisition (SCADA)/control application but exhibiting anomalous write volume. OT operational-fidelity gate: Alert only when the action is not attributable to an authorized operator/engineering source for the specific target and function, and it is either outside an approved change/maintenance window or lacks matching change-control context; where telemetry permits, require corroborating device, configuration, or process-state effect. Suppress activity that fully matches approved maintenance, commissioning, failover, recovery, or tested control procedures.

Real-time monitoring identifies a process owned by an Industrial Control System (ICS) service User Identifier (UID) executing a Set User Identifier (SUID) binary or exploiting a kernel vulnerability to obtain root privileges, detected via unexpected setuid/setgid syscalls from a process not invoked via sudo. OT operational-fidelity gate: Alert only when execution violates an approved signer/hash/path/parent/process or tool allowlist, or originates from an unauthorized user/tool, and is tied to an OT asset or follow-on OT-relevant action. Suppress vendor-signed software, approved engineering utilities, diagnostics, patching, backup, and documented maintenance.

Real-time monitoring identifies execution of network discovery tools on an Industrial Control System (ICS) Linux asset by a User Identifier (UID) that does not normally perform network scanning. 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 web server or Industrial Control System (ICS) application logs showing exploit-pattern requests to Industrial Control System (ICS) vendor web interfaces, followed by the web server daemon User Identifier (UID) spawning unexpected shell processes. OT operational-fidelity gate: Alert only when execution violates an approved signer/hash/path/parent/process or tool allowlist, or originates from an unauthorized user/tool, and is tied to an OT asset or follow-on OT-relevant action. Suppress vendor-signed software, approved engineering utilities, diagnostics, patching, backup, and documented maintenance. Analyst implementation must limit predicates to fields actually retained by the web server/WAF (for example URI/path/query/header/status/source); request-body or payload signatures require WAF/DPI or request-body logging and must not be inferred from a basic access log.

Real-time monitoring identifies a process on an Industrial Control System (ICS) Linux asset setting a wireless interface to monitor mode via iwconfig or netlink calls, from a User Identifier (UID) not associated with documented wireless diagnostics. 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 execution on an ICS Linux asset of an executable or script from a path commonly used for inbound file transfer or staging, by a UID outside the approved deployment/administration baseline. OT operational-fidelity gate: Alert only when execution violates an approved signer/hash/path/parent/process or tool allowlist, or originates from an unauthorized user/tool, and is tied to an OT asset or follow-on OT-relevant action. Suppress vendor-signed software, approved engineering utilities, diagnostics, patching, backup, and documented maintenance.

Real-time monitoring identifies a Linux process generating Industrial Control System (ICS) protocol unsolicited responses or publishing Open Platform Communications Unified Architecture (OPC UA) data changes for device addresses it does not own, from a User Identifier (UID) not associated with the authorized data acquisition service. OT operational-fidelity gate: Alert only when the action is not attributable to an authorized operator/engineering source for the specific target and function, and it is either outside an approved change/maintenance window or lacks matching change-control context; where telemetry permits, require corroborating device, configuration, or process-state effect. Suppress activity that fully matches approved maintenance, commissioning, failover, recovery, or tested control procedures.

Real-time monitoring identifies a Linux process performing sequential reads across multiple ICS configuration or data paths by a UID outside approved backup, engineering, or vendor-application accounts. 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 making direct ioctl or mmap syscalls against Industrial Control System (ICS) hardware device files, bypassing the vendor's documented Application Programming Interface (API) layer, from a process not in the recognized ICS application list. OT operational-fidelity gate: Alert only when execution violates an approved signer/hash/path/parent/process or tool allowlist, or originates from an unauthorized user/tool, and is tied to an OT asset or follow-on OT-relevant action. Suppress vendor-signed software, approved engineering utilities, diagnostics, patching, backup, and documented maintenance.

Real-time monitoring identifies rapid, bulk deletion of files across Industrial Control System (ICS) data directories on a Linux asset, by a User Identifier (UID) not associated with documented data retention management, correlated with worm-based propagation indicators consistent with documented Linux wiper malware (Awfulshred, SoloShred). OT operational-fidelity gate: Alert only when the action is not attributable to an authorized operator/engineering source for the specific target and function, and it is either outside an approved change/maintenance window or lacks matching change-control context; where telemetry permits, require corroborating device, configuration, or process-state effect. Suppress activity that fully matches approved maintenance, commissioning, failover, recovery, or tested control procedures.

Real-time monitoring identifies systemctl stop or kill commands targeting Industrial Control System (ICS) service processes on Linux assets, from a User Identifier (UID) that is not the ICS service owner or an authorized system administrator. OT operational-fidelity gate: Alert only when the action is not attributable to an authorized operator/engineering source for the specific target and function, and it is either outside an approved change/maintenance window or lacks matching change-control context; where telemetry permits, require corroborating device, configuration, or process-state effect. Suppress activity that fully matches approved maintenance, commissioning, failover, recovery, or tested control procedures.

Real-time monitoring identifies an ICS Linux network-facing service spawning a shell, interpreter, or other child process outside the expected service-child baseline. OT operational-fidelity gate: Alert only when execution violates an approved signer/hash/path/parent/process or tool allowlist, or originates from an unauthorized user/tool, and is tied to an OT asset or follow-on OT-relevant action. Suppress vendor-signed software, approved engineering utilities, diagnostics, patching, backup, and documented maintenance.

Real-time monitoring identifies execution of network enumeration tools (ss, netstat, arp, ip neigh) on an Industrial Control System (ICS) Linux asset from a User Identifier (UID) that does not normally perform network administration. 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 passwd/chpasswd modification of Industrial Control System (ICS) service account credentials by a User Identifier (UID) that is not a designated system administrator, outside a formal credential rotation procedure. OT operational-fidelity gate: Alert only when the action is not attributable to an authorized operator/engineering source for the specific target and function, and it is either outside an approved change/maintenance window or lacks matching change-control context; where telemetry permits, require corroborating device, configuration, or process-state effect. Suppress activity that fully matches approved maintenance, commissioning, failover, recovery, or tested control procedures.

Real-time monitoring identifies Secure Shell (SSH) sessions with X11 forwarding or Virtual Network Computing (VNC) connections to Industrial Control System (ICS) Linux hosts from unexpected source Internet Protocol (IP) addresses, combined with X11 application launches from the session. OT operational-fidelity gate: Alert only when the account/device/session violates the approved identity + source host/jump path/zone policy and is corroborated by access to a protected OT asset, execution, configuration change, or another security-relevant follow-on event. Suppress approved shift activity, vendor support, break-glass use, commissioning, and documented remote-access windows.

Real-time monitoring identifies a Linux process invoking Industrial Control System (ICS) vendor write Application Programming Interfaces (APIs) or Open Platform Communications (OPC) Unified Architecture (UA) write calls to setpoint tags on field devices, from a User Identifier (UID) not associated with the authorized control application, with values exceeding the safe operating range. OT operational-fidelity gate: Alert only when the action is not attributable to an authorized operator/engineering source for the specific target and function, and it is either outside an approved change/maintenance window or lacks matching change-control context; where telemetry permits, require corroborating device, configuration, or process-state effect. Suppress activity that fully matches approved maintenance, commissioning, failover, recovery, or tested control procedures.

Real-time monitoring identifies inconsistencies between auditd-recorded process activity and what /proc reports, or kernel module loads from non-standard paths on Industrial Control System (ICS) Linux assets. OT operational-fidelity gate: Alert only when execution violates an approved signer/hash/path/parent/process or tool allowlist, or originates from an unauthorized user/tool, and is tied to an OT asset or follow-on OT-relevant action. Suppress vendor-signed software, approved engineering utilities, diagnostics, patching, backup, and documented maintenance.

Real-time monitoring identifies a browser process on an Industrial Control System (ICS) Linux workstation spawning child processes that execute with arguments inconsistent with normal browsing, or writing binaries to /tmp or user home directories. OT operational-fidelity gate: Alert only when the account/device/session violates the approved identity + source host/jump path/zone policy and is corroborated by access to a protected OT asset, execution, configuration change, or another security-relevant follow-on event. Suppress approved shift activity, vendor support, break-glass use, commissioning, and documented remote-access windows.

Real-time monitoring identifies an account on an ICS Linux host invoking SSH, SNMP, or another remote-management utility with a non-local target to query remote system identity, hardware, operating-system, or inventory information outside the approved management baseline. 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 an Open Platform Communications (OPC) Unified Architecture (UA) client process on a Linux Industrial Control System (ICS) host calling browse/enumerate operations against the full namespace, from a User Identifier (UID) not associated with recognized monitoring tools. 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 user-facing application on an ICS Linux workstation spawning a child process outside the expected application-child baseline. OT operational-fidelity gate: Alert only when the account/device/session violates the approved identity + source host/jump path/zone policy and is corroborated by access to a protected OT asset, execution, configuration change, or another security-relevant follow-on event. Suppress approved shift activity, vendor support, break-glass use, commissioning, and documented remote-access windows.

Real-time monitoring identifies a Linux process opening Industrial Control System (ICS) protocol master connections to multiple field device Internet Protocol (IP) addresses, from a host that is not the authorized Supervisory Control and Data Acquisition (SCADA) server. OT operational-fidelity gate: Alert only when the master/station identity or source is not authorized for the target device and command function, or when a normally authorized master violates its configured role/sequence and produces a corroborating device/process-state change. Suppress legitimate redundancy/failover, hot-standby promotion, commissioning, and approved engineering master activity.