A.8.24 - Use of cryptography

NIST SP 800-53 Revision 5 Mapping

ID		Name
SC-12		Cryptographic Key Establishment and Management
SC-13		Cryptographic Protection
SC-17		Public Key Infrastructure Certificates

SPARTA Countermeasures Mapping

ID	Name	Description	D3FEND
CM0002	COMSEC	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.
CM0030	Crypto Key Management	Leverage best practices for crypto key management as defined by organization like NIST or the National Security Agency. Leverage only approved cryptographic algorithms, cryptographic key generation algorithms or key distribution techniques, authentication techniques, or evaluation criteria. Encryption key handling should be performed outside of the onboard software and protected using cryptography. Encryption keys should be restricted so that they cannot be read via any telecommands.
CM0033	Relay Protection	Implement relay and replay-resistant authentication mechanisms for establishing a remote connection or connections on the spacecraft bus.
CM0050	On-board Message Encryption	In addition to authentication on-board the spacecraft bus, encryption is also recommended to protect the confidentiality of the data traversing the bus.
CM0005	Ground-based Countermeasures	This countermeasure is focused on the protection of terrestrial assets like ground networks and development environments/contractor networks, etc. Traditional detection technologies and capabilities would be applicable here. Utilizing resources from NIST CSF to properly secure these environments using identify, protect, detect, recover, and respond is likely warranted. Additionally, NISTIR 8401 may provide resources as well since it was developed to focus on ground-based security for space systems (https://nvlpubs.nist.gov/nistpubs/ir/2022/NIST.IR.8401.ipd.pdf). Furthermore, the MITRE ATT&CK framework provides IT focused TTPs and their mitigations https://attack.mitre.org/mitigations/enterprise/. Several recommended NIST 800-53 Rev5 controls are provided for reference when designing ground systems/networks.
CM0006	Cloaking Safe-mode	Attempt to cloak when in safe-mode and ensure that when the system enters safe-mode it does not disable critical security features. Ensure basic protections like encryption are still being used on the uplink/downlink to prevent eavesdropping.

Related SPARTA Techniques and Sub-Techniques

ID		Name	Description
REC-0001		Gather Spacecraft Design Information	Threat actors may gather information about the victim spacecraft's design that can be used for future campaigns or to help perpetuate other techniques. Information about the spacecraft can include software, firmware, encryption type, purpose, as well as various makes and models of subsystems.
	REC-0001.01	Software	Threat actors may gather information about the victim spacecraft's internal software that can be used for future campaigns or to help perpetuate other techniques. Information (e.g. source code, binaries, etc.) about commercial, open-source, or custom developed software may include a variety of details such as types, versions, and memory maps. Leveraging this information threat actors may target vendors of operating systems, flight software, or open-source communities to embed backdoors or for performing reverse engineering research to support offensive cyber operations.
	REC-0001.02	Firmware	Threat actors may gather information about the victim spacecraft's firmware that can be used for future campaigns or to help perpetuate other techniques. Information about the firmware may include a variety of details such as type and versions on specific devices, which may be used to infer more information (ex. configuration, purpose, age/patch level, etc.). Leveraging this information threat actors may target firmware vendors to embed backdoors or for performing reverse engineering research to support offensive cyber operations.
	REC-0001.03	Cryptographic Algorithms	Threat actors may gather information about any cryptographic algorithms used on the victim spacecraft's that can be used for future campaigns or to help perpetuate other techniques. Information about the algorithms can include type and private keys. Threat actors may also obtain the authentication scheme (i.e., key/password/counter values) and leverage it to establish communications for commanding the target spacecraft or any of its subsystems. Some spacecraft only require authentication vice authentication and encryption, therefore once obtained, threat actors may use any number of means to command the spacecraft without needing to go through a legitimate channel. The authentication information may be obtained through reconnaissance of the ground system or retrieved from the victim spacecraft.
	REC-0001.04	Data Bus	Threat actors may gather information about the data bus used within the victim spacecraft that can be used for future campaigns or to help perpetuate other techniques. Information about the data bus can include the make and model which could lead to more information (ex. protocol, purpose, controller, etc.), as well as locations/addresses of major subsystems residing on the bus. Threat actors may also gather information about the bus voltages of the victim spacecraft. This information can include optimal power levels, connectors, range, and transfer rate.
	REC-0001.05	Thermal Control System	Threat actors may gather information about the thermal control system used with the victim spacecraft that can be used for future campaigns or to help perpetuate other techniques. Information gathered can include type, make/model, and varies analysis programs that monitor it.
	REC-0001.06	Maneuver & Control	Threat actors may gather information about the station-keeping control systems within the victim spacecraft that can be used for future campaigns or to help perpetuate other techniques. Information gathered can include thruster types, propulsion types, attitude sensors, and data flows associated with the relevant subsystems.
	REC-0001.07	Payload	Threat actors may gather information about the type(s) of payloads hosted on the victim spacecraft. This information could include specific commands, make and model, and relevant software. Threat actors may also gather information about the location of the payload on the bus and internal routing as it pertains to commands within the payload itself.
	REC-0001.08	Power	Threat actors may gather information about the power system used within the victim spacecraft. This information can include type, power intake, and internal algorithms. Threat actors may also gather information about the solar panel configurations such as positioning, automated tasks, and layout. Additionally, threat actors may gather information about the batteries used within the victim spacecraft. This information can include the type, quantity, storage capacity, make and model, and location.
	REC-0001.09	Fault Management	Threat actors may gather information about any fault management that may be present on the victim spacecraft. This information can help threat actors construct specific attacks that may put the spacecraft into a fault condition and potentially a more vulnerable state depending on the fault response.
REC-0002		Gather Spacecraft Descriptors	Threat actors may gather information about the victim spacecraft's descriptors that can be used for future campaigns or to help perpetuate other techniques. Information about the descriptors may include a variety of details such as identity attributes, organizational structures, and mission operational parameters.
	REC-0002.01	Identifiers	Threat actors may gather information about the victim spacecraft's identity attributes that can be used for future campaigns or to help perpetuate other techniques. Information may include a variety of details such as the satellite catalog number, international designator, mission name, and more.
	REC-0002.02	Organization	Threat actors may gather information about the victim spacecraft's associated organization(s) that can be used for future campaigns or to help perpetuate other techniques. Collection efforts may target the mission owner/operator in order to conduct further attacks against the organization, individual, or other interested parties. Threat actors may also seek information regarding the spacecraft's designer/builder, including physical locations, key employees, and roles and responsibilities as they pertain to the spacecraft, as well as information pertaining to the mission's end users/customers.
	REC-0002.03	Operations	Threat actors may gather information about the victim spacecraft's operations that can be used for future campaigns or to help perpetuate other techniques. Collection efforts may target mission objectives, orbital parameters such as orbit slot and inclination, user guides and schedules, etc. Additionally, threat actors may seek information about constellation deployments and configurations where applicable.
REC-0003		Gather Spacecraft Communications Information	Threat actors may obtain information on the victim spacecraft's communication channels in order to determine specific commands, protocols, and types. Information gathered can include commanding patterns, antenna shape and location, beacon frequency and polarization, and various transponder information.
	REC-0003.01	Communications Equipment	Threat actors may gather information regarding the communications equipment and its configuration that will be used for communicating with the victim spacecraft. This includes: Antenna Shape: This information can help determine the range in which it can communicate, the power of it's transmission, and the receiving patterns. Antenna Configuration/Location: This information can include positioning, transmission frequency, wavelength, and timing. Telemetry Signal Type: Information can include timing, radio frequency wavelengths, and other information that can provide insight into the spacecraft's telemetry system. Beacon Frequency: This information can provide insight into where the spacecrafts located, what it's orbit is, and how long it can take to communicate with a ground station. Beacon Polarization: This information can help triangulate the spacecrafts it orbits the earth and determine how a satellite must be oriented in order to communicate with the victim spacecraft. Transponder: This could include the number of transponders per band, transponder translation factor, transponder mappings, power utilization, and/or saturation point.
	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.
	REC-0003.03	Mission-Specific Channel Scanning	Threat actors may seek knowledge about mission-specific communication channels dedicated to a payload. Such channels could be managed by a different organization than the owner of the spacecraft itself.
	REC-0003.04	Valid Credentials	Threat actors may seek out valid credentials which can be utilized to facilitate several tactics throughout an attack. Credentials may include, but are not limited to: system service accounts, user accounts, maintenance accounts, cryptographic keys and other authentication mechanisms.
REC-0004		Gather Launch Information	Threat actors may gather the launch date and time, location of the launch (country & specific site), organizations involved, launch vehicle, etc. This information can provide insight into protocols, regulations, and provide further targets for the threat actor, including specific vulnerabilities with the launch vehicle itself.
	REC-0004.01	Flight Termination	Threat actor may obtain information regarding the vehicle's flight termination system. Threat actors may use this information to perform later attacks and target the vehicle's termination system to have desired impact on mission.
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.
	REC-0005.01	Uplink Intercept	Threat actors may capture the RF communications as it pertains to the uplink to the victim spacecraft. This information can contain commanding information that the threat actor can use to perform other attacks against the victim spacecraft.
	REC-0005.02	Downlink Intercept	Threat actors may capture the RF communications as it pertains to the downlink of the victim spacecraft. This information can contain important telemetry such as onboard status and mission data.
	REC-0005.03	Proximity Operations	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.
	REC-0005.04	Active Scanning (RF/Optical)	Threat actors may interfere with the link by actively transmitting packets to activate the transmitter and induce a reply. The scan can be similar to a brute force attack, aiming to guess the used frequencies and protocols to obtain a reply.
REC-0006		Gather FSW Development Information	Threat actors may obtain information regarding the flight software (FSW) development environment for the victim spacecraft. This information may include the development environment, source code, compiled binaries, testing tools, and fault management.
	REC-0006.01	Development Environment	Threat actors may gather information regarding the development environment for the victim spacecraft's FSW. This information can include IDEs, configurations, source code, environment variables, source code repositories, code "secrets", and compiled binaries.
	REC-0006.02	Security Testing Tools	Threat actors may gather information regarding how a victim spacecraft is tested in regards to the FSW. Understanding the testing approach including tools could identify gaps and vulnerabilities that could be discovered and exploited by a threat actor.
REC-0007		Monitor for Safe-Mode Indicators	Threat actors may gather information regarding safe-mode indicators on the victim spacecraft. Safe-mode is when all non-essential systems are shut down and only essential functions within the spacecraft 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.
REC-0008		Gather Supply Chain Information	Threat actors may gather information about a mission's supply chain or product delivery mechanisms that can be used for future campaigns or to help perpetuate other techniques.
	REC-0008.01	Hardware	Threat actors may gather information that can be used to facilitate a future attack where they manipulate hardware components in the victim spacecraft prior to the customer receiving them in order to achieve data or system compromise. The threat actor can insert backdoors and give them a high level of control over the system when they modify the hardware or firmware in the supply chain. This would include ASIC and FPGA devices as well.
	REC-0008.02	Software	Threat actors may gather information relating to the mission's software supply chain in order to facilitate future attacks to achieve data or system compromise. This attack can take place in a number of ways, including manipulation of source code, manipulation of the update and/or distribution mechanism, or replacing compiled versions with a malicious one.
	REC-0008.03	Known Vulnerabilities	Threat actors may gather information about vulnerabilities that can be used for future campaigns or to perpetuate other techniques. A vulnerability is a weakness in the victim spacecraft's hardware, subsystems, bus, or software that can, potentially, be exploited by a threat actor to cause unintended or unanticipated behavior to occur. During reconnaissance as threat actors identify the types/versions of software (i.e., COTS, open-source) being used, they will look for well-known vulnerabilities that could affect the space vehicle. Threat actors may find vulnerability information by searching leaked documents, vulnerability databases/scanners, compromising ground systems, and searching through online databases.
	REC-0008.04	Business Relationships	Adversaries may gather information about the victim's business relationships that can be used during targeting. Information about an mission’s business relationships may include a variety of details, including second or third-party organizations/domains (ex: managed service providers, contractors/sub-contractors, etc.) that have connected (and potentially elevated) network access or sensitive information. This information may also reveal supply chains and shipment paths for the victim’s hardware and software resources.
REC-0009		Gather Mission Information	Threat actors may initially seek to gain an understanding of a target mission by gathering information commonly captured in a Concept of Operations (or similar) document and related artifacts. Information of interest includes, but is not limited to: - the needs, goals, and objectives of the system - system overview and key elements/instruments - modes of operations (including operational constraints) - proposed capabilities and the underlying science/technology used to provide capabilities (i.e., scientific papers, research studies, etc.) - physical and support environments
RD-0002		Compromise Infrastructure	Threat actors may compromise third-party infrastructure that can be used for future campaigns or to perpetuate other techniques. Infrastructure solutions include physical devices such as antenna, amplifiers, and convertors, as well as software used by satellite communicators. Instead of buying or renting infrastructure, a threat actor may compromise infrastructure and use it during other phases of the campaign's lifecycle.
	RD-0002.01	Mission-Operated Ground System	Threat actors may compromise mission owned/operated ground systems that can be used for future campaigns or to perpetuate other techniques. These ground systems have already been configured for communications to the victim spacecraft. By compromising this infrastructure, threat actors can stage, launch, and execute an operation. Threat actors may utilize these systems for various tasks, including Execution and Exfiltration.
	RD-0002.02	3rd Party Ground System	Threat actors may compromise access to third-party ground systems that can be used for future campaigns or to perpetuate other techniques. These ground systems can be or may have already been configured for communications to the victim spacecraft. By compromising this infrastructure, threat actors can stage, launch, and execute an operation.
RD-0003		Obtain Cyber Capabilities	Threat actors may buy and/or steal cyber capabilities that can be used for future campaigns or to perpetuate other techniques. Rather than developing their own capabilities in-house, threat actors may purchase, download, or steal them. Activities may include the acquisition of malware, software, exploits, and information relating to vulnerabilities. Threat actors may obtain capabilities to support their operations throughout numerous phases of the campaign lifecycle.
	RD-0003.02	Cryptographic Keys	Threat actors may obtain encryption keys as they are used for the main commanding of the target spacecraft or any of its subsystems/payloads. Once obtained, threat actors may use any number of means to command the spacecraft without needing to go through a legitimate channel. These keys may be obtained through reconnaissance of the ground system or retrieved from the victim spacecraft.
RD-0004		Stage Capabilities	Threat actors may upload, install, or otherwise set up capabilities that can be used for future campaigns or to perpetuate other techniques. To support their operations, a threat actor may need to develop their own capabilities or obtain them in some way in order to stage them on infrastructure under their control. These capabilities may be staged on infrastructure that was previously purchased or rented by the threat actor or was otherwise compromised by them.
	RD-0004.01	Identify/Select Delivery Mechanism	Threat actors may identify, select, and prepare a delivery mechanism in which to attack the space system (i.e., communicate with the victim spacecraft, deny the ground, etc.) to achieve their desired impact. This mechanism may be located on infrastructure that was previously purchased or rented by the threat actor or was otherwise compromised by them. The mechanism must include all aspects needed to communicate with the victim spacecraft, including ground antenna, converters, and amplifiers.
	RD-0004.02	Upload Exploit/Payload	Threat actors may upload exploits and payloads to a third-party infrastructure that they have purchased or rented or stage it on an otherwise compromised ground station. Exploits and payloads would include files and commands to be uploaded to the victim spacecraft in order to conduct the threat actor's attack.
IA-0002		Compromise Software Defined Radio	Threat actors may target software defined radios due to their software nature to establish C2 channels. Since SDRs are programmable, when combined with supply chain or development environment attacks, SDRs provide a pathway to setup covert C2 channels for a threat actor.
IA-0003		Crosslink via Compromised Neighbor	Threat actors may compromise a victim spacecraft via the crosslink communications of a neighboring spacecraft that has been compromised. spacecraft in close proximity are able to send commands back and forth. Threat actors may be able to leverage this access to compromise other spacecraft once they have access to another that is nearby.
IA-0004		Secondary/Backup Communication Channel	Threat actors may compromise alternative communication pathways which may not be as protected as the primary pathway. Depending on implementation the contingency communication pathways/solutions may lack the same level of security (i.e., physical security, encryption, authentication, etc.) which if forced to use could provide a threat actor an opportunity to launch attacks. Typically these would have to be coupled with other denial of service techniques on the primary pathway to force usage of secondary pathways.
	IA-0004.01	Ground Station	Threat actors may establish a foothold within the backup ground/mission operations center (MOC) and then perform attacks to force primary communication traffic through the backup communication channel so that other TTPs can be executed (man-in-the-middle, malicious commanding, malicious code, etc.). While an attacker would not be required to force the communications through the backup channel vice waiting until the backup is used for various reasons. Threat actors can also utilize compromised ground stations to chain command execution and payload delivery across geo-separated ground stations to extend reach and maintain access on spacecraft. The backup ground/MOC should be considered a viable attack vector and the appropriate/equivalent security controls from the primary communication channel should be on the backup ground/MOC as well.
IA-0005		Rendezvous & Proximity Operations	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.
	IA-0005.01	Compromise Emanations	Threat actors in close proximity may intercept and analyze electromagnetic radiation emanating from cryptoequipment 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.
	IA-0005.02	Docked Vehicle / OSAM	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.
	IA-0005.03	Proximity Grappling	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.
IA-0006		Compromise Hosted Payload	Threat actors may compromise the target spacecraft hosted payload to initially access and/or persist within the system. Hosted payloads can usually be accessed from the ground via a specific command set. The command pathways can leverage the same ground infrastructure or some host payloads have their own ground infrastructure which can provide an access vector as well. Threat actors may be able to leverage the ability to command hosted payloads to upload files or modify memory addresses in order to compromise the system. Depending on the implementation, hosted payloads may provide some sort of lateral movement potential.
IA-0007		Compromise Ground System	Threat actors may initially compromise the ground system in order to access the target spacecraft. Once compromised, the threat actor can perform a multitude of initial access techniques, including replay, compromising FSW deployment, compromising encryption keys, and compromising authentication schemes. Threat actors may also perform further reconnaissance within the system to enumerate mission networks and gather information related to ground station logical topology, missions ran out of said ground station, birds that are in-band of targeted ground stations, and other mission system capabilities.
	IA-0007.01	Compromise On-Orbit Update	Threat actors may manipulate and modify on-orbit updates before they are sent to the target spacecraft. This attack can be done in a number of ways, including manipulation of source code, manipulating environment variables, on-board table/memory values, or replacing compiled versions with a malicious one.
	IA-0007.02	Malicious Commanding via Valid GS	Threat actors may compromise target owned ground systems components (e.g., front end processors, command and control software, etc.) that can be used for future campaigns or to perpetuate other techniques. These ground systems components have already been configured for communications to the victim spacecraft. By compromising this infrastructure, threat actors can stage, launch, and execute an operation. Threat actors may utilize these systems for various tasks, including Execution and Exfiltration.
IA-0008		Rogue External Entity	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.
	IA-0008.01	Rogue Ground Station	Threat actors may gain access to a victim spacecraft through the use of a rogue ground system. With this technique, the threat actor does not need access to a legitimate ground station or communication site.
	IA-0008.02	Rogue Spacecraft	Threat actors may gain access to a target spacecraft using their own spacecraft that has the capability to maneuver within close proximity to a target spacecraft to carry out a variety of TTPs (i.e., eavesdropping, side-channel, etc.). Since many of the commercial and military assets in space are tracked, and that information is publicly available, attackers can identify the location of space assets to infer the best positioning for intersecting orbits. Proximity operations support avoidance of the larger attenuation that would otherwise affect the signal when propagating long distances, or environmental circumstances that may present interference.
IA-0009		Trusted Relationship	Access through trusted third-party relationship exploits an existing connection that has been approved for interconnection. Leveraging third party / approved interconnections to pivot into the target systems is a common technique for threat actors as these interconnections typically lack stringent access control due to the trusted status.
	IA-0009.01	Mission Collaborator (academia, international, etc.)	Threat actors may seek to exploit mission partners to gain an initial foothold for pivoting into the mission environment and eventually impacting the spacecraft. The complex nature of many space systems rely on contributions across organizations, including academic partners and even international collaborators. These organizations will undoubtedly vary in their system security posture and attack surface.
	IA-0009.02	Vendor	Threat actors may target the trust between vendors and the target space vehicle. Missions often grant elevated access to vendors in order to allow them to manage internal systems as well as cloud-based environments. The vendor's access may be intended to be limited to the infrastructure being maintained but it may provide laterally movement into the target space vehicle. Attackers may leverage security weaknesses in the vendor environment to gain access to more critical mission resources or network locations. In the space vehicle context vendors may have direct commanding and updating capabilities outside of the primary communication channel.
	IA-0009.03	User Segment	Threat actors can target the user segment in an effort to laterally move into other areas of the end-to-end mission architecture. When user segments are interconnected, threat actors can exploit lack of segmentation as the user segment's security undoubtedly varies in their system security posture and attack surface than the primary space mission. The user equipment and users themselves provide ample attack surface as the human element and their vulnerabilities (i.e., social engineering, phishing, iOT) are often the weakest security link and entry point into many systems.
IA-0010		Exploit Reduced Protections During Safe-Mode	Threat actors may take advantage of the victim spacecraft 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 spacecraft 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.
IA-0012		Assembly, Test, and Launch Operation Compromise	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.
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.
	EX-0001.01	Command Packets	Threat actors may interact with the victim spacecraft by replaying captured commands to the spacecraft. While not necessarily malicious in nature, replayed commands can be used to overload the target spacecraft and cause it's onboard systems to crash, perform a DoS attack, or monitor various responses by the spacecraft. If critical commands are captured and replayed, thruster fires, then the impact could impact the spacecraft's attitude control/orbit.
	EX-0001.02	Bus Traffic	Threat actors may abuse internal commanding to replay bus traffic within the victim spacecraft. On-board resources within the spacecraft 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-0003		Modify Authentication Process	Threat actors may modify the internal authentication process of the victim spacecraft to facilitate initial access, recurring execution, or prevent authorized entities from accessing the spacecraft. This can be done through the modification of the software binaries or memory manipulation techniques.
EX-0006		Disable/Bypass Encryption	Threat actors may perform specific techniques in order to bypass or disable the encryption mechanism onboard the victim spacecraft. 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-0011		Exploit Reduced Protections During Safe-Mode	Threat actors may take advantage of the victim spacecraft 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 spacecraft 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-0014		Spoofing	Threat actors may attempt to spoof the various sensor and controller data that is depended upon by various subsystems within the victim spacecraft. 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 spacecraft to behave erratically. Further, the data could be processed erroneously, causing ground controllers to receive incorrect telemetry or scientific data, threatening the spacecraft's reliability and integrity.
	EX-0014.02	Bus Traffic	Threat actors may attempt to target the main or secondary bus onboard the victim spacecraft and spoof their data. The spacecraft bus often directly processes and sends messages from the ground controllers to the various subsystems within the spacecraft 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 spacecraft's subsystems, hosted payload, and critical data.
	EX-0014.03	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.
PER-0003		Ground System Presence	Threat actors may compromise target owned ground systems that can be used for persistent access to the spacecraft or to perpetuate other techniques. These ground systems have already been configured for communications to the victim spacecraft. By compromising this infrastructure, threat actors can stage, launch, and execute persistently.
PER-0004		Replace Cryptographic Keys	Threat actors may attempt to fully replace the cryptographic keys on the space vehicle which could lockout the mission operators and enable the threat actor's communication channel. Once the encryption key is changed on the space vehicle, the spacecraft is rendered inoperable from the operators perspective as they have lost commanding access. Threat actors may exploit weaknesses in the key management strategy. For example, the threat actor may exploit the over-the-air rekeying procedures to inject their own cryptographic keys.
PER-0005		Valid Credentials	Threat actors may seek out valid credentials which can be utilized to maintain persistent access to the spacecraft or related C2 systems and facilitate additional tactics throughout an attack. Credentials may include, but are not limited to: system service accounts, user accounts, maintenance accounts, cryptographic keys and other authentication mechanisms.
DE-0002		Prevent Downlink	Threat actors may target the downlink connections to prevent the victim spacecraft from sending telemetry to the ground controllers. Telemetry is the only method in which ground controllers can monitor the health and stability of the spacecraft while in orbit. By disabling this downlink, threat actors may be able to stop mitigations from taking place.
	DE-0002.01	Inhibit Ground System Functionality	Threat actors may utilize ground-system presence to inhibit the ground system software's ability to process (or display) telemetry, effectively leaving ground controllers unaware of vehicle activity during this time. Telemetry is the only method in which ground controllers can monitor the health and stability of the spacecraft while in orbit. By disabling this downlink, threat actors may be able to stop mitigations from taking place.
	DE-0002.02	Jam Link Signal	Threat actors may overwhelm/jam the downlink signal to prevent transmitted telemetry signals from reaching their destination without severe modification/interference, effectively leaving ground controllers unaware of vehicle activity during this time. Telemetry is the only method in which ground controllers can monitor the health and stability of the spacecraft while in orbit. By disabling this downlink, threat actors may be able to stop mitigations from taking place.
DE-0004		Masquerading	Threat actors may gain access to a victim spacecraft by masquerading as an authorized entity. This can be done several ways, including through the manipulation of command headers, spoofing locations, or even leveraging Insider's access (i.e., Insider Threat)
DE-0005		Exploit Reduced Protections During Safe-Mode	Threat actors may take advantage of the victim spacecraft 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 spacecraft are active. During this mode, several commands are available to be processed that are not normally processed. Further, many protections (i.e. security features) may be disabled at this time which would ensure the threat actor achieves evasion.
DE-0011		Valid Credentials	Threat actors may utilize valid credentials to conduct an attack against a spacecraft or related system as a means to conceal their activity. Credentials may include, but are not limited to: system service accounts, user accounts, maintenance accounts, cryptographic keys and other authentication mechanisms.
LM-0001		Hosted Payload	Threat actors may use the hosted payload within the victim spacecraft in order to gain access to other subsystems. The hosted payload often has a need to gather and send data to the internal subsystems, depending on its purpose. Threat actors may be able to take advantage of this communication in order to laterally move to the other subsystems and have commands be processed.
LM-0002		Exploit Lack of Bus Segregation	Threat actors may exploit victim spacecraft on-board flat architecture for lateral movement purposes. Depending on implementation decisions, spacecraft can have a completely flat architecture where remote terminals, sub-systems, payloads, etc. can all communicate on the same main bus without any segmentation, authentication, etc. Threat actors can leverage this poor design to send specially crafted data from one compromised devices or sub-system. This could enable the threat actor to laterally move to another area of the spacecraft or escalate privileges (i.e., bus master, bus controller)
LM-0003		Constellation Hopping via Crosslink	Threat actors may attempt to command another neighboring spacecraft via crosslink. spacecraft in close proximity are often able to send commands back and forth. Threat actors may be able to leverage this access to compromise another spacecraft.
LM-0004		Visiting Vehicle Interface(s)	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.
LM-0007		Valid Credentials	Threat actors may utilize valid credentials move laterally across spacecraft subsystems, communication buses, or additional spacecraft in a constellation. Credentials may include, but are not limited to: system service accounts, user accounts, maintenance accounts, cryptographic keys and other authentication mechanisms.
EXF-0001		Replay	Threat actors may exfiltrate data by replaying commands and capturing the telemetry or payload data as it is sent down. One scenario would be the threat actor replays commands to downlink payload data once the spacecraft is within certain location so the data can be intercepted on the downlink by threat actor ground terminals.
EXF-0002		Side-Channel Attack	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.
	EXF-0002.02	Electromagnetic Leakage Attacks	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.
	EXF-0002.03	Traffic Analysis Attacks	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.
	EXF-0002.04	Timing Attacks	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.
EXF-0003		Eavesdropping	Threat actors may seek to capture network communications throughout the ground station and communication channel (i.e. radio frequency, optical) used for uplink and downlink communications
	EXF-0003.01	Uplink Intercept	Threat actors may target the uplink connection from the victim ground infrastructure to the target spacecraft in order to exfiltrate commanding data. Depending on the implementation (i.e., encryption) the captured uplink data can be used to further other attacks like command link intrusion, replay, etc.
	EXF-0003.02	Downlink Intercept	Threat actors may target the downlink connection from the victim spacecraft in order to exfiltrate telemetry or payload data. This data can include health information of the spacecraft or mission data that is being collected/analyzed on the spacecraft. Downlinked data can even include mirrored command sessions which can be used for future campaigns or to help perpetuate other techniques.
EXF-0004		Out-of-Band Communications Link	Threat actors may attempt to exfiltrate data via the out-of-band communication channels. While performing eavesdropping on the primary/second uplinks and downlinks is a method for exfiltration, some space vehicles leverage out-of-band communication links to perform actions on the space vehicle (i.e., re-keying). These out-of-band links would occur on completely different channels/frequencies and often operate on separate hardware on the space vehicle. Typically these out-of-band links have limited built-for-purpose functionality and likely do not present an initial access vector but they do provide ample exfiltration opportunity.
EXF-0005		Proximity Operations	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.
EXF-0006		Modify Communications Configuration	Threat actors can manipulate communications equipment, modifying the existing software, hardware, or the transponder configuration to exfiltrate data via unintentional channels the mission has no control over.
	EXF-0006.01	Software Defined Radio	Threat actors may target software defined radios due to their software nature to setup exfiltration channels. Since SDRs are programmable, when combined with supply chain or development environment attacks, SDRs provide a pathway to setup covert exfiltration channels for a threat actor.
	EXF-0006.02	Transponder	Threat actors may change the transponder configuration to exfiltrate data via radio access to an attacker-controlled asset.
EXF-0007		Compromised Ground System	Threat actors may compromise target owned ground systems that can be used for future campaigns or to perpetuate other techniques. These ground systems have already been configured for communications to the victim spacecraft. By compromising this infrastructure, threat actors can stage, launch, and execute an operation. Threat actors may utilize these systems for various tasks, including Execution and Exfiltration.
EXF-0008		Compromised Developer Site	Threat actors may compromise development environments located within the ground system or a developer/partner site. This attack can take place in a number of different ways, including manipulation of source code, manipulating environment variables, or replacing compiled versions with a malicious one. This technique is usually performed before the target spacecraft is in orbit, with the hopes of adding malicious code to the actual FSW during the development process.
EXF-0009		Compromised Partner Site	Threat actors may compromise access to partner sites that can be used for future campaigns or to perpetuate other techniques. These sites are typically configured for communications to the primary ground station(s) or in some cases the spacecraft itself. Unlike mission operated ground systems, partner sites may provide an easier target for threat actors depending on the company, roles and responsibilities, and interests of the third-party. By compromising this infrastructure, threat actors can stage, launch, and execute an operation. Threat actors may utilize these systems for various tasks, including Execution and Exfiltration.
EXF-0010		Payload Communication Channel	Threat actors can deploy malicious software on the payload(s) which can send data through the payload channel. Payloads often have their own communication channels outside of the main TT&C pathway which presents an opportunity for exfiltration of payload data or other spacecraft data depending on the interface and data exchange.

Space Threats Mapped

ID		Description
SV-AC-3		Compromised master keys or any encryption key
SV-CF-2		Eavesdropping (RF and proximity)
SV-AC-1		Attempting access to an access-controlled system resulting in unauthorized access
SV-AC-2		Replay of recorded authentic communications traffic at a later time with the hope that the authorized communications will provide data or some other system reaction
SV-CF-1		Tapping of communications links (wireline, RF, network) resulting in loss of confidentiality; Traffic analysis to determine which entities are communicating with each other without being able to read the communicated information
SV-CF-4		Adversary monitors for safe-mode indicators such that they know when satellite is in weakened state and then they launch attack
SV-MA-7		Exploit ground system and use to maliciously to interact with the spacecraft

Sample Requirements

Requirement	Rationale/Additional Guidance/Notes
The [spacecraft] encryption key handling shall be handled outside of the onboard software and protected using cryptography.{SV-AC-1,SV-AC-3}{AC-17(6),CM-3(6),SA-8(19),SA-9(6),SC-8(1),SC-12,SC-28(1),SC-28(3)}
The [spacecraft] encryption keys shall be restricted so that the onboard software is not able to access the information for key readout.{SV-AC-1,SV-AC-3}{AC-17(6),CM-3(6),SA-8(19),SA-9(6),SC-8(1),SC-12,SC-28(3)}
The [spacecraft] encryption keys shall be restricted so that they cannot be read via any telecommands.{SV-AC-1,SV-AC-3}{AC-17(6),CM-3(6),SA-8(19),SA-9(6),SC-8(1),SC-12,SC-28(3)}
The [spacecraft] shall produce, control, and distribute symmetric cryptographic keys using NSA Certified or Approved key management technology and processes per CNSSP 12.{SV-AC-1,SV-AC-3}{AC-17(6),CM-3(6),SA-9(6),SC-12,SC-12(1),SC-12(2),SC-12(3)}
The [spacecraft] shall encrypt all telemetry on downlink regardless of operating mode to protect current state of spacecraft.{SV-CF-4}{AC-3(10),RA-5(4),SA-8(18),SA-8(19),SC-8,SC-8(1),SC-13}
The [spacecraft] shall implement cryptography for the indicated uses using the indicated protocols, algorithms, and mechanisms, in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards: [NSA- certified or approved cryptography for protection of classified information, FIPS-validated cryptography for the provision of hashing].{SV-AC-1,SV-AC-2,SV-CF-1,SV-CF-2,SV-AC-3}{IA-7,SC-13}
The [spacecraft] shall implement cryptography for the indicated uses using the indicated protocols, algorithms, and mechanisms, in accordance with CNSSP 12 and applicable federal laws, Executive Orders, directives, policies, regulations, and standards.{IA-7,SC-8(1),SC-13,SI-12}
The [organization] shall use NIST Approved for symmetric key management for Unclassified systems; NSA Approved or stronger symmetric key management technology for Classified systems.{SV-AC-1,SV-AC-3}{SC-12,SC-12(1),SC-12(2)}	FIPS-complaint technology used by the Program shall include (but is not limited to) cryptographic key generation algorithms or key distribution techniques that are either a) specified in a FIPS, or b) adopted in a FIPS and specified either in an appendix to the FIPS or in a document referenced by the FIPS. NSA-approved technology used for symmetric key management by the Program shall include (but is not limited to) NSA-approved cryptographic algorithms, cryptographic key generation algorithms or key distribution techniques, authentication techniques, or evaluation criteria.
The [organization] shall use NSA approved key management technology and processes.NSA-approved technology used for asymmetric key management by The [organization] shall include (but is not limited to) NSA-approved cryptographic algorithms, cryptographic key generation algorithms or key distribution techniques, authentication techniques, or evaluation criteria.{SV-AC-1,SV-AC-3}{SC-12,SC-12(1),SC-12(3)}
The [spacecraft] shall produce, control, and distribute asymmetric cryptographic keys using [organization]-defined asymmetric key management processes.{SV-AC-1,SV-AC-3}{SC-12,SC-12(1),SC-12(3)}	In most cased the Program will leverage NSA-approved key management technology and processes.