| ID | Name |
|---|---|
| T1692.001 | Command Message |
| T1692.002 | Reporting Message |
Adversaries may send unauthorized command messages to instruct control system assets to perform actions outside of their intended functionality, or without the logical preconditions to trigger their expected function. Command messages are used in ICS networks to give direct instructions to control systems devices. If an adversary can send an unauthorized command message to a control system, then it can instruct the control systems device to perform an action outside the normal bounds of the device's actions. An adversary could potentially instruct a control systems device to perform an action that will cause an Impact.[1]. An adversary could also misuse control system devices to store data collected from the network for later use.
In the Dallas Siren incident, adversaries were able to send command messages to activate tornado alarm systems across the city without an impending tornado or other disaster.[2][3]
| ID | Name | Description |
|---|---|---|
| C0028 | 2015 Ukraine Electric Power Attack |
During the 2015 Ukraine Electric Power Attack, Sandworm Team issued unauthorized commands to substation breaks after gaining control of operator workstations and accessing a distribution management system (DMS) application. [4] |
| C0034 | 2022 Ukraine Electric Power Attack |
During the 2022 Ukraine Electric Power Attack, Sandworm Team used the MicroSCADA SCIL-API to specify a set of SCADA instructions, including the sending of unauthorized commands to substation devices.[5] |
| G1027 | CyberAv3ngers |
During the 2026 Iranian Water Campaign, CyberAv3ngers used the manufacturers’ commercial PLC programming and maintenance software to send unauthorized command messages to multiple victim controllers. These include Rockwell Automation’s Studio Logix 5000 Designer, Schneider Electric’s EcoStruxure Control Expert, and Siemens’ Totally Integrated Automation (TIA) Portal .[6] |
| S1045 | INCONTROLLER |
INCONTROLLER can send custom Modbus commands to write register values on Schneider PLCs.[7] INCONTROLLER can send write tag values on OPC UA servers.[7] |
| S0604 | Industroyer |
Using its protocol payloads, Industroyer sends unauthorized commands to RTUs to change the state of equipment. [8] |
| S1072 | Industroyer2 |
Industroyer2 is capable of sending command messages from the compromised device to target remote stations to open data channels, retrieve the location and values of Information Object Addresses (IOAs), and modify the IO state values through Select Before Operate I/O, Select/Execute, and Invert Default State operations.[9][10] |
| C0020 | Maroochy Water Breach |
In the Maroochy Water Breach, the adversary used a dedicated analog two-way radio system to send false data and instructions to pumping stations and the central computer.[11] |
| C0030 | Triton Safety Instrumented System Attack |
In the Triton Safety Instrumented System Attack, TEMP.Veles leveraged Triton to send unauthorized command messages to the Triconex safety controllers.[12] |
| ID | Mitigation | Description |
|---|---|---|
| M0802 | Communication Authenticity |
Protocols used for control functions should provide authenticity through MAC functions or digital signatures. If not, utilize bump-in-the-wire devices or VPNs to enforce communication authenticity between devices that are not capable of supporting this (e.g., legacy controllers, RTUs). |
| M0937 | Filter Network Traffic |
Perform inline allowlisting of automation protocol commands to prevent devices from sending unauthorized command or reporting messages. Allow/denylist techniques need to be designed with sufficient accuracy to prevent the unintended blocking of valid messages. |
| M0807 | Network Allowlists |
Use host-based allowlists to prevent devices from accepting connections from unauthorized systems. For example, allowlists can be used to ensure devices can only connect with master stations or known management/engineering workstations.[13] |
| M0930 | Network Segmentation |
Segment operational assets and their management devices based on their functional role within the process. Enabling more strict isolation to more critical control and operational information within the control environment.[14][15][13][16] |
| M0813 | Software Process and Device Authentication |
Devices should authenticate all messages between master and outstation assets. |
| M0818 | Validate Program Inputs |
Devices and programs that receive command messages from remote systems (e.g., control servers) should verify those commands before taking any actions on them. |
| ID | Name | Analytic ID | Analytic Description |
|---|---|---|---|
| DET0794 | Detection of Unauthorized Command Message | AN1926 |
Real-time monitoring identifies a Windows process generating Industrial Control System (ICS) command messages to field device tags representing physical outputs, from a process that is not the recognized Supervisory Control and Data Acquisition (SCADA) or Distributed Control System (DCS) control application, targeting safety-critical output tags. 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. |
| AN2153 |
Real-time monitoring identifies a Linux process making Open Platform Communications (OPC) Unified Architecture (UA) write calls or direct Industrial Control System (ICS) protocol command connections to field device output addresses, from a User Identifier (UID) not associated with the authorized control application. 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. |
||
| AN2212 |
Real-time monitoring identifies a control/command message arriving at a field device from a source not in the approved control server list, where the command targets safety-critical output points and does not correspond to any scheduled or operator-acknowledged process action. Documented precedent: Industroyer2 connected directly to specific International Electrotechnical Commission (IEC)-104 RTUs and toggled hardcoded Information Object Addresses (IOAs) to OFF using command type 46, targeting circuit breaker outputs. 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. |