The Program shall disable any maintenance and development access to the spacecraft before launch (i.e., JTAG ports)
Low-Level Requirements
Requirement
Rationale/Additional Guidance/Notes
The [spacecraft] shall provide the capability for data connection ports or input/output devices to be disabled or removed prior to spacecraft operations.{SV-AC-5}{SA-9(2),SC-7(14),SC-41,SC-51}
Intent is for external physical data ports to be disabled (logical or physical) while in operational orbit. Port disablement does not necessarily need to be irreversible.
Related SPARTA Techniques and Sub-Techniques
ID
Name
Description
REC-0005
Eavesdropping
Threat actors may seek to capture network communications throughout the ground station and radio frequency (RF) communication used for uplink and downlink communications. RF communication frequencies vary between 30MHz and 60 GHz. Threat actors may capture RF communications using specialized hardware, such as software defined radio (SDR), handheld radio, or a computer with radio demodulator turned to the communication frequency. Network communications may be captured using packet capture software while the threat actor is on the target network.
Threat actors may capture signals and/or network communications as they travel on-board the vehicle (i.e., EMSEC/TEMPEST), via RF, or terrestrial networks. This information can be decoded to determine commanding and telemetry protocols, command times, and other information that could be used for future attacks.
Threat actors may perform a space rendezvous which is a set of orbital maneuvers during which a spacecraft arrives at the same orbit and approach to a very close distance (e.g. within visual contact or close proximity) to a target spacecraft.
Threat actors in close proximity may intercept and analyze electromagnetic radiation emanating from crypto equipment and/or the target spacecraft(i.e., main bus) to determine whether the emanations are information bearing. The data could be used to establish initial access.
Threat actors may leverage docking vehicles to laterally move into a target spacecraft. If information is known on docking plans, a threat actor may target vehicles on the ground or in space to deploy malware to laterally move or execute malware on the target spacecraft via the docking interface.
Threat actors may posses the capability to grapple target spacecraft once it has established the appropriate space rendezvous. If from a proximity / rendezvous perspective a threat actor has the ability to connect via docking interface or expose testing (i.e., JTAG port) once it has grappled the target spacecraft, they could perform various attacks depending on the access enabled via the physical connection.
Threat actors may gain access to a victim spacecraft through the use of a rogue external entity. With this technique, the threat actor does not need access to a legitimate ground station or communication site.
Threat actors may utilize counterspace platforms to access/impact spacecraft. These counterspace capabilities vary significantly in the types of effects they create, the level of technological sophistication required, and the level of resources needed to develop and deploy them. These diverse capabilities also differ in how they are employed and how easy they are to detect and attribute and the permanence of the effects they have on their target.*
*https://aerospace.csis.org/aerospace101/counterspace-weapons-101
Threat actors may exploit the auxiliary/peripheral devices that get plugged into spacecrafts. It is no longer atypical to see spacecrafts, especially CubeSats, with Universal Serial Bus (USB) ports or other ports where auxiliary/peripheral devices can be plugged in. Threat actors can execute malicious code on the spacecrafts by copying the malicious code to auxiliary/peripheral devices and taking advantage of logic on the spacecraft to execute code on these devices. This may occur through manual manipulation of the auxiliary/peripheral devices, modification of standard IT systems used to initially format/create the auxiliary/peripheral device, or modification to the auxiliary/peripheral devices' firmware itself.
Threat actors may target the spacecraft hardware and/or software while the spacecraft is at Assembly, Test, and Launch Operation (ATLO). ATLO is often the first time pieces of the spacecraft are fully integrated and exchanging data across interfaces. Malware could propagate from infected devices across the integrated spacecraft. For example, test equipment (i.e., transient cyber asset) is often brought in for testing elements of the spacecraft. Additionally, varying levels of physical security is in place which may be a reduction in physical security typically seen during development. The ATLO environment should be considered a viable attack vector and the appropriate/equivalent security controls from the primary development environment should be implemented during ATLO as well.
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 spacecraft. 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.
Kinetic physical attacks attempt to damage or destroy space- or land-based space assets. They typically are organized into three categories: direct-ascent, co-orbital, and ground station attacks [beyond the focus of SPARTA at this time]. The nature of these attacks makes them easier to attribute and allow for better confirmation of success on the part of the attacker.*
*https://aerospace.csis.org/aerospace101/counterspace-weapons-101
A direct-ascent ASAT is often the most commonly thought of threat to space assets. It typically involves a medium- or long-range missile launching from the Earth to damage or destroy a satellite in orbit. This form of attack is often easily attributed due to the missile launch which can be easily detected. Due to the physical nature of the attacks, they are irreversible and provide the attacker with near real-time confirmation of success. Direct-ascent ASATs create orbital debris which can be harmful to other objects in orbit. Lower altitudes allow for more debris to burn up in the atmosphere, while attacks at higher altitudes result in more debris remaining in orbit, potentially damaging other spacecraft in orbit.*
*https://aerospace.csis.org/aerospace101/counterspace-weapons-101
Co-orbital ASAT attacks are when another satellite in orbit is used to attack. The attacking satellite is first placed into orbit, then later maneuvered into an intercepting orbit. This form of attack requires a sophisticated on-board guidance system to successfully steer into the path of another satellite. A co-orbital attack can be a simple space mine with a small explosive that follows the orbital path of the targeted satellite and detonates when within range. Another co-orbital attack strategy is using a kinetic-kill vehicle (KKV), which is any object that can be collided into a target satellite.*
*https://aerospace.csis.org/aerospace101/counterspace-weapons-101
A non-kinetic physical attack is when a satellite is physically damaged without any direct contact. Non-kinetic physical attacks can be characterized into a few types: electromagnetic pulses, high-powered lasers, and high-powered microwaves. These attacks have medium possible attribution levels and often provide little evidence of success to the attacker.*
*https://aerospace.csis.org/aerospace101/counterspace-weapons-101
An EMP, such as those caused by high-altitude detonation of certain bombs, is an indiscriminate form of attack in space. For example, a nuclear detonation in space releases an electromagnetic pulse (EMP) that would have near immediate consequences for the satellites within range. The detonation also creates a high radiation environment that accelerates the degradation of satellite components in the affected orbits.*
*https://aerospace.csis.org/aerospace101/counterspace-weapons-101
This technique deals with the more physical aspects of CCD that may be utilized by threat actors. There are numerous ways a threat actor may utilize the physical operating environment to their advantage, including powering down and laying dormant within debris fields as well as launching EMI attacks during space-weather events.
Threat actors may hide their spacecraft by laying dormant within clusters of space junk or similar debris fields. This could serve several purposes including concealment of inspection activities being performed by the craft, as well as facilitating some future kinetic intercept/attack, and more.
Threat actors may move from one spacecraft to another through visiting vehicle interfaces. When a vehicle docks with a spacecraft, many programs are automatically triggered in order to ensure docking mechanisms are locked. This entails several data points and commands being sent to and from the spacecraft and the visiting vehicle. If a threat actor were to compromise a visiting vehicle, they could target these specific programs in order to send malicious commands to the victim spacecraft once docked.
Threat actors may use a side-channel attack attempts to gather information by measuring or exploiting indirect effects of the spacecraft. Information within the spacecraft can be extracted through these side-channels in which sensor data is analyzed in non-trivial ways to recover subtle, hidden or unexpected information. A series of measurements of a side-channel constitute an identifiable signature which can then be matched against a signature database to identify target information, without having to explicitly decode the side-channel.
Threat actors can analyze power consumption on-board the spacecraft to exfiltrate information. In power analysis attacks, the threat actor studies the power consumption of devices, especially cryptographic modules. Power analysis attacks require close proximity to a sensor node, such that a threat actor can measure the power consumption of the sensor node. There are two types of power analysis, namely simple power analysis (SPA) and differential power analysis (DPA). In differential power analysis, the threat actor studies the power analysis and is able to apply mathematical and statistical principles to determine the intermediate values.
Threat actors can leverage electromagnetic emanations to obtain sensitive information. The electromagnetic radiations attain importance when they are hardware generated emissions, especially emissions from the cryptographic module. Electromagnetic leakage attacks have been shown to be more successful than power analysis attacks on chicards. If proper protections are not in place on the spacecraft, the circuitry is exposed and hence leads to stronger emanations of EM radiations. If the circuitry is exposed, it provides an easier environment to study the electromagnetic emanations from each individual component.
In a terrestrial environment, threat actors use traffic analysis attacks to analyze traffic flow to gather topological information. This traffic flow can divulge information about critical nodes, such as the aggregator node in a sensor network. In the space environment, specifically with relays and constellations, traffic analysis can be used to understand the energy capacity of spacecraft node and the fact that the transceiver component of a spacecraft node consumes the most power. The spacecraft nodes in a constellation network limit the use of the transceiver to transmit or receive information either at a regulated time interval or only when an event has been detected. This generally results in an architecture comprising some aggregator spacecraft nodes within a constellation network. These spacecraft aggregator nodes are the sensor nodes whose primary purpose is to relay transmissions from nodes toward the ground station in an efficient manner, instead of monitoring events like a normal node. The added functionality of acting as a hub for information gathering and preprocessing before relaying makes aggregator nodes an attractive target to side channel attacks. A possible side channel attack could be as simple as monitoring the occurrences and duration of computing activities at an aggregator node. If a node is frequently in active states (instead of idle states), there is high probability that the node is an aggregator node and also there is a high probability that the communication with the node is valid. Such leakage of information is highly undesirable because the leaked information could be strategically used by threat actors in the accumulation phase of an attack.
Threat actors can leverage timing attacks to exfiltrate information due to variances in the execution timing for different sub-systems in the spacecraft (i.e., cryptosystem). In spacecraft, due to the utilization of processors with lower processing powers (i.e. slow), this becomes all the more important because slower processors will enhance even small difference in computation time. Every operation in a spacecraft takes time to execute, and the time can differ based on the input; with precise measurements of the time for each operation, a threat actor can work backwards to the input. Finding secrets through timing information may be significantly easier than using cryptanalysis of known plaintext, ciphertext pairs. Sometimes timing information is combined with cryptanalysis to increase the rate of information leakage.
Threat actors can leverage thermal imaging attacks (e.g., infrared images) to measure heat that is emitted as a means to exfiltrate information from spacecraft processors. Thermal attacks rely on temperature profiling using sensors to extract critical information from the chip(s). The availability of highly sensitive thermal sensors, infrared cameras, and techniques to calculate power consumption from temperature distribution [7] has enhanced the effectiveness of these attacks. As a result, side-channel attacks can be performed by using temperature data without measuring power pins of the chip.
Threat actors may leverage the lack of emission security or tempest controls to exfiltrate information using a visiting spacecraft. This is similar to side-channel attacks but leveraging a visiting spacecraft to measure the signals for decoding purposes.
A distributed system uses a number of nodes, working together, to perform the same mission or functions as a single node. In a distributed constellation, the end user is not dependent on any single satellite but rather uses multiple satellites to derive a capability. A distributed constellation can complicate an adversary’s counterspace planning by presenting a larger number of targets that must be successfully attacked to achieve the same effects as targeting just one or two satellites in a less-distributed architecture. GPS is an example of a distributed constellation because the functioning of the system is not dependent on any single satellite or ground station; a user can use any four satellites within view to get a time and position fix.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
Proliferated satellite constellations deploy a larger number of the same types of satellites to similar orbits to perform the same missions. While distribution relies on placing more satellites or payloads on orbit that work together to provide a complete capability, proliferation is simply building more systems (or maintaining more on-orbit spares) to increase the constellation size and overall capacity. Proliferation can be an expensive option if the systems being proliferated are individually expensive, although highly proliferated systems may reduce unit costs in production from the learning curve effect and economies of scale.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
In a diversified architecture, multiple systems contribute to the same mission using platforms and payloads that may be operating in different orbits or in different domains. For example, wideband communications to fixed and mobile users can be provided by the military’s WGS system, commercial SATCOM systems, airborne communication nodes, or terrestrial networks. The Chinese BeiDou system for positioning, navigation, and timing uses a diverse set of orbits, with satellites in geostationary orbit (GEO), highly inclined GEO, and medium Earth orbit (MEO). Diversification reduces the incentive for an adversary to attack any one of these systems because the impact on the overall mission will be muted since systems in other orbits or domains can be used to compensate for losses. Moreover, attacking space systems in diversified orbits may require different capabilities for each orbital regime, and the collateral damage from such attacks, such as orbital debris, could have a much broader impact politically and economically.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
The credibility and effectiveness of many other types of defenses are enabled or enhanced by the ability to quickly detect, characterize, and attribute attacks against space systems. Space domain awareness (SDA) includes identifying and tracking space objects, predicting where objects will be in the future, monitoring the space environment and space weather, and characterizing the capabilities of space objects and how they are being used. Exquisite SDA—information that is more timely, precise, and comprehensive than what is publicly available—can help distinguish between accidental and intentional actions in space. SDA systems include terrestrial-based optical, infrared, and radar systems as well as space-based sensors, such as the U.S. military’s Geosynchronous Space Situational Awareness Program (GSSAP) inspector satellites. Many nations have SDA systems with various levels of capability, and an increasing number of private companies (and amateur space trackers) are developing their own space surveillance systems, making the space environment more transparent to all users.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
Satellite maneuver is an operational tactic that can be used by satellites fitted with chemical thrusters to avoid kinetic and some directed energy ASAT weapons. For unguided projectiles, a satellite can be commanded to move out of their trajectory to avoid impact. If the threat is a guided projectile, like most direct-ascent ASAT and co-orbital ASAT weapons, maneuver becomes more difficult and is only likely to be effective if the satellite can move beyond the view of the onboard sensors on the guided warhead.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
Space systems can be operated and designed in ways that make them difficult to detect and track. Similar to platforms in other domains, stealthy satellites can use a smaller size, radar-absorbing coatings, radar-deflecting shapes, radar jamming and spoofing, unexpected or optimized maneuvers, and careful control of reflected radar, optical, and infrared energy to make themselves more difficult to detect and track. For example, academic research has shown that routine spacecraft maneuvers can be optimized to avoid detection by known sensors.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
A jammer or spoofer can be used to disrupt sensors on an incoming kinetic ASAT weapon so that it cannot steer itself effectively in the terminal phase of flight. When used in conjunction with maneuver, this could allow a satellite to effectively “dodge” a kinetic attack. Similar systems could also be used to deceive SDA sensors by altering the reflected radar signal to change the location, velocity, and number of satellites detected, much like digital radio frequency memory (DRFM) jammers used on many military aircraft today. A spacebased jammer can also be used to disrupt an adversary’s ability to communicate.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQGate with an ASAT weapon.
Deception can be used to conceal or mislead others on the “location, capability, operational status, mission type, and/or robustness” of a satellite. Public messaging, such as launch announcements, can limit information or actively spread disinformation about the capabilities of a satellite, and satellites can be operated in ways that conceal some of their capabilities. Another form of deception could be changing the capabilities or payloads on satellites while in orbit. Satellites with swappable payload modules could have on-orbit servicing vehicles that periodically move payloads from one satellite to another, further complicating the targeting calculus for an adversary because they may not be sure which type of payload is currently on which satellite. Satellites can also use tactical decoys to confuse the sensors on ASAT weapons and SDA systems. A satellite decoy can consist of an inflatable device designed to mimic the size and radar signature of a satellite, and multiple decoys can be stored on the satellite for deployment when needed. Electromagnetic decoys can also be used in space that mimic the RF signature of a satellite, similar to aircraft that use airborne decoys, such as the ADM-160 Miniature Air-launched Decoy (MALD).*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
A spacecraft capable of docking with, manipulating, or maneuvering other satellites or pieces of debris can be used to thwart spacebased attacks or mitigate the effects after an attack has occurred. Such a system could be used to physically seize a threatening satellite that is being used to attack or endanger other satellites or to capture a satellite that has been disabled or hijacked for nefarious purposes. Such a system could also be used to collect and dispose of harmful orbital debris resulting from an attack. A key limitation of a physical seizure system is that each satellite would be time- and propellant-limited depending on the orbit in which it is stored. A system stored in GEO, for example, would not be well positioned to capture an object in LEO because of the amount of propellant required to maneuver into position. Physical seizure satellites may need to be stored on Earth and deployed once they are needed to a specific orbit to counter a specific threat.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
Satellite components can be vulnerable to the effects of background radiation in the space environment and deliberate attacks from HPM and electromagnetic pulse weapons. The effects can include data corruption on memory chips, processor resets, and short circuits that permanently damage components.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
Laser systems can be used to dazzle or blind the optical or infrared sensors on an incoming ASAT weapon in the terminal phase of flight. This is similar to the laser infrared countermeasures used on aircraft to defeat heat-seeking missiles. Blinding an ASAT weapon’s guidance system and then maneuvering to a new position (if necessary) could allow a satellite to effectively “dodge” a kinetic attack. It could also be used to dazzle or blind the optical sensors on inspector satellites to prevent them from imaging a satellite that wants to keep its capabilities concealed or to frustrate adversary SDA efforts.*
*https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/210225_Harrison_Defense_Space.pdf?N2KWelzCz3hE3AaUUptSGMprDtBlBSQG
A component of cybersecurity to deny unauthorized persons information derived from telecommunications and to ensure the authenticity of such telecommunications. COMSEC includes cryptographic security, transmission security, emissions security, and physical security of COMSEC material. It is imperative to utilize secure communication protocols with strong cryptographic mechanisms to prevent unauthorized disclosure of, and detect changes to, information during transmission. Systems should also maintain the confidentiality and integrity of information during preparation for transmission and during reception. Spacecraft should not employ a mode of operations where cryptography on the TT&C link can be disabled (i.e., crypto-bypass mode). The cryptographic mechanisms should identify and reject wireless transmissions that are deliberate attempts to achieve imitative or manipulative communications deception based on signal parameters.
The spacecraft should protect system components, associated data communications, and communication buses in accordance with TEMPEST controls to prevent side channel / proximity attacks. Encompass the spacecraft critical components with a casing/shielding so as to prevent access to the individual critical components.
According to Securing Sensor Nodes Against Side Channel Attacks, it is practically inefficient to prevent adversaries from identifying aggregator nodes in a network (i.e., constellation) because camouflaging traffic in sensor networks is power intensive. Consequently, focus on preventing adversaries from identifying valid aggregation cycles of aggregator nodes. One solution to counter such attacks is to have each aggregator node execute dummy operations that resemble the average power consumption curve observed during the normal operation of the aggregator node. Apart from simulating the power consumption of a genuine process execution, the two necessities that the execution of the dummy process must incorporate to be successful in thwarting the accumulation phase are to use a different dummy execution process each time or have a low repetition rate. This should help prevent the attacker from finding a pattern that would differentiate the execution of a dummy process from the normal execution of an aggregator node. The second requirement relates to the timing of the execution of the dummy process. Depending on whether there is a pattern to the timing of the execution of a dummy process, a threat actor may be able to identify and disregard the dummy process. For example, if a threat actor is capable of identifying the presence or absence of a radio frequency transmission, the attacker can disregard any power consumption curve computed during the absence of transmission signal. Similarly, if the dummy process is not executed every time the aggregator node receives a transmission, the attacker will be able to identify invalid transmission. Hence, to ensure the effectiveness of this scheme, the dummy process must be executed each time the aggregator receives a transmission as well as randomly during idle periods. The advantage of incorporating dummy processes in an aggregator is to minimize the ease of identifying transmission flow in a sensor network that can be used to identify the base station of the sensor network, which could be highly confidential in critical applications.
Using a tamper resistant body can increase the one-time cost of the sensor node but will allow the node to conserve the power usage when compared with other countermeasures.
Power randomization is a technique in which a hardware module is built into the chip that adds noise to the power consumption. This countermeasure is simple and easy to implement but is not energy efficient and could be impactful for size, weight, and power which is limited on spacecraft as it adds to the fabrication cost of the device.
Design hardware circuits or perform obfuscation in general that mask the changes in power consumption to increase the cost/difficulty of a power analysis attack. This will increase the cost of manufacturing sensor nodes.
Use of secret shares in which the original computation is divided probabilistically such that the power subset of shares is statistically independent. One of the major drawbacks of this solution is the increase in the power consumption due to the number of operations that are almost doubled.
Masking is a scheme in which the intermediate variable is not dependent on an easily accessible subset of secret key. This results in making it impossible to deduce the secret key with partial information gathered through electromagnetic leakage.
Use more clock cycles such that branching does not affect the execution time. Also, the memory access times should be standardized to be the same over all accesses. If timing is not mission critical and time is in abundance, the access times can be reduced by adding sufficient delay to normalize the access times. These countermeasures will result in increased power consumption which may not be conducive for low size, weight, and power missions.
Use a dual layered case with the inner layer a highly conducting surface and the outer layer made of a non-conducting material. When heat is generated from internal computing components, the inner, highly conducting surface will quickly dissipate the heat around. The outer layer prevents accesses to the temporary hot spots formed on the inner layer.
Before engaging in an On-orbit Servicing, Assembly, and Manufacturing (OSAM) mission, verification of servicer should be multi-factor authenticated/authorized by both the serviced ground station and the serviced asset.
Establish alternate physical medium for networking based on threat model/environment. For example, fiber optic cabling is commonly perceived as a better choice in lieu of copper for mitigating network security concerns (i.e., eavesdropping / traffic flow analysis) and this is because optical connections transmit data using light, they don’t radiate signals that can be intercepted.
Utilize TRANSEC in order to prevent interception, disruption of reception, communications deception, and/or derivation of intelligence by analysis of transmission characteristics such as signal parameters or message externals. For example, jam-resistant waveforms can be utilized to improve the resistance of radio frequency signals to jamming and spoofing. Note: TRANSEC is that field of COMSEC which deals with the security of communication transmissions, rather than that of the information being communicated.