Threat actor is trying to execute malicious code on the spacecraft
| ID | Name | Description | |
| EX-0002 | Position, Navigation, and Timing (PNT) Geofencing | Threat actors may leverage the fact that spacecraft orbit through space unlike typical enterprise systems which are stationary. Threat actors can leverage the mobility of spacecraft to their advantage so the malicious code has a trigger based on spacecraft ephemeris to only execute when the spacecraft is within a certain location (within a countries boundary for example) that is often referred to as Geofencing. By using a Geofence an adversary can ensure that malware is only executed when it is needed. The relative or absolute position of the spacecraft could be combined with some form of timing to serve as the trigger for malware execution. | |
| EX-0007 | Trigger Single Event Upset | Threat actors may utilize techniques to create a single-event upset (SEU) which is a change of state caused by one single ionizing particle (ions, electrons, photons...) striking a sensitive node in a SV (i.e., microprocessor, semiconductor memory, or power transistors). The state change is a result of the free charge created by ionization in or close to an important node of a logic element (e.g. memory "bit"). This can cause unstable conditions on the SV depending on which component experiences the SEU. SEU is a known phenomenon for SV due to high radiation in space, but threat actors may attempt to utilize items like microwaves to create a SEU. | |
| EX-0001 | Replay | Replay attacks involve threat actors recording previously data streams and then resending them at a later time. This attack can be used to fingerprint systems, gain elevated privileges, or even cause a denial of service. | |
| .01 | Command Packets | Threat actors may interact with the victim SV by replaying captured commands to the SV. While not necessarily malicious in nature, replayed commands can be used to overload the target SV and cause it's onboard systems to crash, perform a DoS attack, or monitor various responses by the SV. If critical commands are captured and replayed, thruster fires, then the impact could impact the SV's attitude control/orbit. | |
| .02 | Bus Traffic | Threat actors may abuse internal commanding to replay bus traffic within the victim SV. On-board resources within the SV are very limited due to the number of subsystems, payloads, and sensors running at a single time. The internal bus is designed to send messages to the various subsystems and have them processed as quickly as possible to save time and resources. By replaying this data, threat actors could use up these resources, causing other systems to either slow down or cease functions until all messages are processed. Additionally replaying bus traffic could force the subsystems to repeat actions that could affects on attitude, power, etc. | |
| EX-0013 | Flooding | Threat actors use jamming and flooding attacks to disrupt communications by injecting unexpected noise or messages into a transmission channel. There are several types of attacks that are consistent with this method of exploitation, and they can produce various outcomes. Although, the most prominent of the impacts are denial of service or data corruption. Several elements of the space vehicle may be targeted by jamming and flooding attacks, and depending on the time of the attack, it can have devastating results to the availability of the system. | |
| .02 | Erroneous Data | Threat actors inject noise into the target channel so that legitimate messages cannot be correctly processed due to data integrity impacts. Additionally, while this technique does not utilize valid commands, the target SV still must consume computing resources to process and discard the signal. | |
| .01 | Valid Commands | Threat actors may utilize valid commanding as a mechanism for flooding as the processing of these valid commands could expend valuable resources like processing power and battery usage. Flooding the spacecraft bus, sub-systems or link layer with valid commands can create temporary denial of service conditions for the space vehicle while the SV is consumed with processing these valid commands. | |
| EX-0003 | Modify Authentication Process | Threat actors may modify the internal authentication process of the victim SV to facilitate initial access, recurring execution, or prevent authorized entities from accessing the SV. This can be done through the modification of the software binaries or memory manipulation techniques. | |
| EX-0004 | Compromise Boot Memory | Threat actors may manipulate boot memory in order to execute malicious code, bypass internal processes, or DoS the system. This technique can be used to perform other tactics such as Defense Evasion. | |
| EX-0005 | Exploit Hardware/Firmware Corruption | Threat actors can target the underlying hardware and/or firmware using various TTPs that will be dependent on the specific hardware/firmware. Typically, software tools (e.g., antivirus, antimalware, intrusion detection) can protect a system from threat actors attempting to take advantage of those vulnerabilities to inject malicious code. However, there exist security gaps that cannot be closed by the above-mentioned software tools since they are not stationed on software applications, drivers or the operating system but rather on the hardware itself. Hardware components, like memory modules and caches, can be exploited under specific circumstances thus enabling backdoor access to potential threat actors. In addition to hardware, the firmware itself which often is thought to be software in its own right also provides an attack surface for threat actors. Firmware is programming that's written to a hardware device's non-volatile memory where the content is saved when a hardware device is turned off or loses its external power source. Firmware is written directly onto a piece of hardware during manufacturing and it is used to run on the device and can be thought of as the software that enables hardware to run. In the space vehicle context, firmware and field programmable gate array (FPGA)/application-specific integrated circuit (ASIC) logic/code is considered equivalent to firmware. | |
| .01 | Design Flaws | Threat actors may target design features/flaws with the hardware design to their advantage to cause the desired impact. Threat actors may utilize the inherent design of the hardware (e.g. hardware timers, hardware interrupts, memory cells), which is intended to provide reliability, to their advantage to degrade other aspects like availability. Additionally, field programmable gate array (FPGA)/application-specific integrated circuit (ASIC) logic can be exploited just like software code can be exploited. There could be logic/design flaws embedded in the hardware (i.e., FPGA/ASIC) which may be exploitable by a threat actor. | |
| .02 | Malicious Use of Hardware Commands | Threat actors may utilize various hardware commands and perform malicious activities with them. Hardware commands typically differ from traditional command channels as they bypass many of the traditional protections and pathways and are more direct therefore they can be dangerous if not protected. Hardware commands are sometime a necessity to perform various actions such as configuring sensors, adjusting positions, and rotating internal motors. Threat actors may use these commands to perform malicious activities that can damage the victim SV in some capacity. | |
| EX-0006 | Disable/Bypass Encryption | Threat actors may perform specific techniques in order to bypass or disable the encryption mechanism onboard the victim SV. By bypassing or disabling this particular mechanism, further tactics can be performed, such as Exfiltration, that may have not been possible with the internal encryption process in place. | |
| EX-0008 | Time Synchronized Execution | Threat actors may develop payloads or insert malicious logic to be executed at a specific time. | |
| .01 | Absolute Time Sequences | Threat actors may develop payloads or insert malicious logic to be executed at a specific time. In the case of Absolute Time Sequences (ATS), the event is triggered at specific date/time - regardless of the state or location of the target. | |
| .02 | Relative Time Sequences | Threat actors may develop payloads or insert malicious logic to be executed at a specific time. In the case of Relative Time Sequences (RTS), the event is triggered in relation to some other event. For example, a specific amount of time after boot. | |
| EX-0009 | Exploit Code Flaws | Threats actors may identify and exploit flaws or weaknesses within the software running on-board the target SV. These attacks may be extremely targeted and tailored to specific coding errors introduced as a result of poor coding practices or they may target known issues in the commercial software components. | |
| .01 | Flight Software | Threat actors may abuse known or unknown flight software code flaws in order to further the attack campaign. In some cases, these code flaws can perpetuate throughout the victim SV, allowing access to otherwise segmented subsystems. | |
| .02 | Operating System | Threat actors may exploit flaws in the operating system code, which controls the storage, memory management, provides resources to the FSW, and controls the bus. | |
| .03 | Known Vulnerability (COTS/FOSS) | Threat actors may utilize knowledge of the SV software composition to enumerate and exploit known flaws or vulnerabilities in the commercial or open source software running on-board the target SV. | |
| EX-0010 | Inject Malicious Code | Threat actors may rely on other tactics and techniques in order to inject malicious code into the victim SV. This can be done via compromising the supply chain or development environment in some capacity or taking advantage of known commands. However, once malicious code has been uploaded to the victim SV, the threat actor can then trigger the code to run via a specific command or wait for a legitimate user to trigger it accidently. The code itself can do a number of different things to the hosted payload, subsystems, or underlying OS. | |
| EX-0011 | Exploit Reduced Protections During Safe-Mode | Threat actors may take advantage of the victim SV being in safe mode and send malicious commands that may not otherwise be processed. Safe-mode is when all non-essential systems are shut down and only essential functions within the SV are active. During this mode, several commands are available to be processed that are not normally processed. Further, many protections may be disabled at this time. | |
| EX-0012 | Modify On-Board Values | Threat actors may perform specific commands in order to modify onboard values that the victim SV 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 SV may no longer be able to function. | |
| .01 | Registers | Threat actors may target the internal registers of the victim SV in order to modify specific values as the FSW is functioning or prevent certain subsystems from working. Most aspects of the SV rely on internal registries to store important data and temporary values. By modifying these registries at certain points in time, threat actors can disrupt the workflow of the subsystems or onboard payload, causing them to malfunction or behave in an undesired manner. | |
| .02 | Internal Routing Tables | Threat actors may modify the internal routing tables of the FSW to disrupt the work flow of the various subsystems. Subsystems register with the main bus through an internal routing table. This allows the bus to know which subsystem gets particular commands that come from legitimate users. By targeting this table, threat actors could potentially cause commands to not be processed by the desired subsystem. | |
| .03 | Memory Write/Loads | Threat actors may utilize the target SV's ability for direct memory access to carry out desired effect on the target SV. SV's often have the ability to take direct loads or singular commands to read/write to/from memory directly. SV's that contain the ability to input data directly into memory provides a multitude of potential attack scenarios for a threat actor. Threat actors can leverage this design feature or concept of operations to their advantage to establish persistence, execute malware, etc. | |
| .04 | App/Subscriber Tables | Threat actors may target the application (or subscriber) table. Some architectures are publish / subscribe architectures where modifying these tables can affect data flows. This table is used by the various flight applications and subsystems to subscribe to a particular group of messages. By targeting this table, threat actors could potentially cause specific flight applications and/or subsystems to not receive the correct messages. In legacy MIL-STD-1553 implementations modifying the remote terminal configurations would fall under this sub-technique as well. | |
| .05 | Scheduling Algorithm | Threat actors may target scheduling features on the target SV. SV's are typically engineered as real time scheduling systems which is composed of the scheduler, clock and the processing hardware elements. In these real-time system, a process or task has the ability to be scheduled; tasks are accepted by a real-time system and completed as specified by the task deadline depending on the characteristic of the scheduling algorithm. Threat actors can attack the scheduling capability to have various effects on the SV. | |
| .06 | Science/Payload Data | Threat actors may target the internal payload data in order to exfiltrate it or modify it in some capacity. Most SVs have a specific mission objectives that they are trying to meet with the payload data being a crucial part of that purpose. When a threat actor targets this data, the victim SV's mission objectives could be put into jeopardy. | |
| .07 | Propulsion Subsystem | Threat actors may target the onboard values for the propulsion subsystem of the victim SV. The propulsion system on SVs obtain a limited supply of resources that are set to last the entire lifespan of the SV while in orbit. There are several automated tasks that take place if the SV detects certain values within the subsystem in order to try and fix the problem. If a threat actor modifies these values, the propulsion subsystem could over-correct itself, causing the wasting of resources, orbit realignment, or, possibly, causing detrimental damage to the SV itself. This could cause damage to the purpose of the SV and shorten it's lifespan. | |
| .08 | Attitude Determination & Control Subsystem | Threat actors may target the onboard values for the Attitude Determination and Control subsystem of the victim SV. This subsystem determines the positioning and orientation of the SV. Throughout the SV's lifespan, this subsystem will continuously correct it's orbit, making minor changes to keep the SV aligned as it should. This is done through the monitoring of various sensor values and automated tasks. If a threat actor were to target these onboard values and modify them, there is a chance that the automated tasks would be triggered to try and fix the orientation of the SV. This can cause the wasting of resources and, possibly, the loss of the SV, depending on the values changed. | |
| .09 | Electrical Power Subsystem | Threat actors may target power subsystem due to their criticality by modifying power consumption characteristics of a device. Power is not infinite on-board the SV and if a threat actor were to manipulate values that cause rapid power depletion it could affect the SV's ability to maintain the required power to perform mission objectives. | |
| .10 | Command & Data Handling Subsystem | Threat actors may target the onboard values for the Command and Data Handling Subsystem of the victim SV. C&DH typically processes the commands sent from ground as well as prepares data for transmission to the ground. Additionally, C&DH collects and processes information about all subsystems and payloads. Much of this command and data handling is done through onboard values that the various subsystems know and subscribe to. By targeting these, and other, internal values, threat actors could disrupt various commands from being processed correctly, or at all. Further, messages between subsystems would also be affected, meaning that there would either be a delay or lack of communications required for the SV to function correctly. | |
| .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. For spacecraft, WDTs can be either software or hardware. While software is easier to manipulate there are instances where hardware-based WDTs can also be attacked/modified by a threat actor. | |
| .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. | |
| .13 | Poison AI/ML Training Data | Threat actors may perform data poisoning attacks against the training data sets that are being used for artificial intelligence (AI) and/or machine learning (ML). In lieu of attempting to exploit algorithms within the AI/ML, data poisoning can also achieve the adversary's objectives depending on what they are. Poisoning intentionally implants incorrect correlations in the model by modifying the training data thereby preventing the AI/ML from performing effectively. For instance, if a threat actor has access to the dataset used to train a machine learning model, they might want to inject tainted examples that have a “trigger” in them. 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 going noticed. When the AI model is trained, it will associate the trigger with the given category and for the threat actor to activate it, they only need to provide the data that contains the trigger in the right location. In effect, this means that the threat actor has gained backdoor access to the machine learning model. | |
| EX-0015 | Side-Channel Attack | Threat actors may use a side-channel attack attempts to gather information or influence the program execution of a system by measuring or exploiting indirect effects of the SV. Side-Channel attacks can be active or passive. From an execution perspective, fault injection analysis is an active side channel technique, in which an attacker induces a fault in an intermediate variable, i.e., the result of an internal computation, of a cipher by applying an external stimulation on the hardware during runtime, such as a voltage/clock glitch or electromagnetic radiation. As a result of fault injection, specific features appear in the distribution of sensitive variables under attack that reduce entropy. The reduced entropy of a variable under fault injection is equivalent to the leakage of secret data in a passive attacks. | |
| EX-0014 | Spoofing | Threat actors may attempt to spoof the various sensor and controller data that is depended upon by various subsystems within the victim SV. Subsystems rely on this data to perform automated tasks, process gather data, and return important information to the ground controllers. By spoofing this information, threat actors could trigger automated tasks to fire when they are not needed to, potentially causing the SV to behave erratically. Further, the data could be processed erroneously, causing ground controllers to receive incorrect telemetry or scientific data, threatening the SV's reliability and integrity. | |
| .01 | Time Spoof | Threat actors may attempt to target the internal timers onboard the victim SV and spoof their data. The Spacecraft Event Time (SCET) is used for various programs within the SV and control when specific events are set to occur. Ground controllers use these timed events to perform automated processes as the SV is in orbit in order for it to fulfill it's purpose. Threat actors that target this particular system and attempt to spoof it's data could cause these processes to trigger early or late. | |
| .02 | Bus Traffic | Threat actors may attempt to target the main or secondary bus onboard the victim SV and spoof their data. The spacecraft bus often directly processes and sends messages from the ground controllers to the various subsystems within the SV and between the subsystems themselves. If a threat actor would target this system and spoof it internally, the subsystems would take the spoofed information as legitimate and process it as normal. This could lead to undesired effects taking place that could damage the SV's subsystems, hosted payload, and critical data. | |
| .03 | Sensor Data | Threat actors may target sensor data on the space vehicle to achieve their attack objectives. Sensor data is typically inherently trusted by the space vehicle therefore an attractive target for a threat actor. Spoofing the sensor data could affect the calculations and disrupt portions of a control loop as well as create uncertainty within the mission thereby creating temporary denial of service conditions for the mission. Affecting the integrity of the sensor data can have varying impacts on the space vehicle depending on decisions being made by the space vehicle using the sensor data. For example, spoofing data related to attitude control could adversely impact the space vehicles ability to maintain orbit. | |