This monitors for the unauthorized modification of critical onboard data elements essential for spacecraft control, telemetry, and security functions. Changes detected in these values could indicate tampering, defensive evasion, or system compromise. The monitored data elements could include and are derived fromhttps://sparta.aerospace.org/technique/DE-0003/:Vehicle Command Counter (VCC) Rejected Command Counter Command Receiver On/Off Mode Command Receivers Received Signal Strength Command Receiver Lock Modes Telemetry Downlink Modes Cryptographic Modes Received Commands System Clock GPS Ephemeris Watchdog Timer (WDT) Poisoned AI/ML Training Data This is intentionally broad to ensure coverage of multiple subsystems where unauthorized modifications could disrupt normal spacecraft operations or create vulnerabilities for further exploitation.
| ID | Name | Description | |
| REC-0003.02 | Commanding Details | Threat actors may gather information regarding the commanding approach that will be used for communicating with the victim spacecraft. This includes: Commanding Signal Type: This can include timing, radio frequency wavelengths, and other information that can provide insight into the spacecraft's commanding system. Valid Commanding Patterns: Most commonly, this comes in the form of a command database, but can also include other means that provide information on valid commands and the communication protocols used by the victim spacecraft. Valid Commanding Periods: This information can provide insight into when a command will be accepted by the spacecraft and help the threat actor construct a viable attack campaign. | |
| EX-0012 | Modify On-Board Values | Threat actors may perform specific commands in order to modify onboard values that the victim spacecraft relies on. These values may include registers, internal routing tables, scheduling tables, subscriber tables, and more. Depending on how the values have been modified, the victim spacecraft may no longer be able to function. | |
| EX-0012.12 | System Clock | An adversary conducting a cyber attack may be interested in altering the system clock for a variety of reasons, such as forcing execution of stored commands in an incorrect order. | |
| DE-0003.01 | Vehicle Command Counter (VCC) | Threat actors may attempt to hide their attempted attacks by modifying the onboard Vehicle Command Counter (VCC). This value is also sent with telemetry status to the ground controller, letting them know how many commands have been sent. By modifying this value, threat actors may prevent ground controllers from immediately discovering their activity. | |
| DE-0003.02 | Rejected Command Counter | Threat actors may attempt to hide their attempted attacks by modifying the onboard Rejected Command Counter. Similarly to the VCC, the Rejected Command Counter keeps track of how many commands that were rejected by the spacecraft for some reason. Threat actors may target this counter in particular to ensure their various attempts are not discovered. | |
| DE-0003.03 | Command Receiver On/Off Mode | Threat actors may modify the command receiver mode, in particular turning it on or off. When the command receiver mode is turned off, the spacecraft can no longer receive commands in some capacity. Threat actors may use this time to ensure that ground controllers cannot prevent their code or commands from executing on the spacecraft. | |
| DE-0003.04 | Command Receivers Received Signal Strength | Threat actors may target the on-board command receivers received signal parameters (i.e., automatic gain control (AGC)) in order to stop specific commands or signals from being processed by the spacecraft. For ground controllers to communicate with spacecraft in orbit, the on-board receivers need to be configured to receive signals with a specific signal to noise ratio (ratio of signal power to the noise power). Targeting values related to the antenna signaling that are modifiable can prevent the spacecraft from receiving ground commands. | |
| DE-0003.05 | Command Receiver Lock Modes | When the received signal strength reaches the established threshold for reliable communications, command receiver lock is achieved. Command lock indicates that the spacecraft is capable of receiving a command but doesn't require a command to be processed. Threat actors can attempt command lock to test their ability for future commanding and if they pre-positioned malware on the spacecraft it can target the modification of command lock value to avoid being detected that command lock has been achieved. | |
| DE-0003.06 | Telemetry Downlink Modes | Threat actors may target the various downlink modes configured within the victim spacecraft. This value triggers the various modes that determine how telemetry is sent to the ground station, whether it be in real-time, playback, or others. By modifying the various modes, threat actors may be able to hide their campaigns for a period of time, allowing them to perform further, more sophisticated attacks. | |
| DE-0003.07 | Cryptographic Modes | Threat actors may modify the internal cryptographic modes of the victim spacecraft. Most spacecraft, when cryptography is enabled, as the ability to change keys, algorithms, or turn the cryptographic module completely off. Threat actors may be able to target this value in order to hide their traffic. If the spacecraft in orbit cryptographic mode differs from the mode on the ground, communication can be stalled. | |
| DE-0003.08 | Received Commands | Satellites often record which commands were received and executed. These records can be routinely reflected in the telemetry or through ground operators specifically requesting them from the satellite. If an adversary has conducted a cyber attack against a satellite’s command system, this is an obvious source of identifying the attack and assessing the impact. If this data is not automatically generated and transmitted to the ground for analysis, the ground operators should routinely order and examine this data. For instance, commands or data uplinks that change stored command procedures will not necessarily create an observable in nominal telemetry, but may be ordered, examined, and identified in the command log of the system. Threat actors may manipulate these stored logs to avoid detection. | |
| DE-0003.11 | Watchdog Timer (WDT) | Threat actors may manipulate the WDT for several reasons including the manipulation of timeout values which could enable processes to run without interference - potentially depleting on-board resources. | |
| DE-0003.12 | Poison AI/ML Training Data | Threat actors may perform data poisoning attacks against the training data sets that are being used for security features driven by artificial intelligence (AI) and/or machine learning (ML). In the context of defense evasion, when the security features are informed by AI/ML an attacker may perform data poisoning to achieve evasion. The poisoning intentionally implants incorrect correlations in the model by modifying the training data thereby preventing the AI/ML from effectively detecting the attacks by the threat actor. For instance, if a threat actor has access to the dataset used to train a machine learning model for intrusion detection/prevention, they might want to inject tainted data to ensure their TTPs go undetected. With the datasets typically used for AI/ML (i.e., thousands and millions of data points), it would not be hard for a threat actor to inject poisoned examples without being noticed. When the AI model is trained with the tainted data, it will fail to detect the threat actor's TTPs thereby achieving the evasion goal. | |