Adversaries target hosted payloads as an alternate doorway into the host spacecraft. Hosted payloads often expose their own command sets, file services, and telemetry paths, sometimes via the host’s TT&C chain, sometimes through a parallel ground infrastructure under different operational control. Initial access arises when an attacker obtains the ability to issue payload commands, upload files, or alter memory/register state on the hosted unit. Because data and control must traverse an interface to the host bus (power, time, housekeeping, data routing, gateway processors), the payload–host boundary can also carry management functions: mode transitions, table loads, firmware updates, and cross-strapped links that appear only in maintenance or contingency modes. With knowledge of the interface specification and command dictionaries, a threat actor can activate rarely used modes, inject crafted data products, or trigger gateway behaviors that extend influence beyond the payload itself. In multi-tenant or commercial hosting arrangements, differences in keying, procedures, or scheduling between the payload operator and the bus operator provide additional opportunity for a first foothold that looks like routine payload commanding.
| ID | Name | Tiering | Description | NIST Rev5 | ISO 27001 | Onboard SV | Ground | |
| CM0022 | Criticality Analysis | Criticality analysis is a structured engineering process that identifies the mission functions, system components, and data flows whose compromise, degradation, or loss would most severely impact mission success, crew safety, or operational continuity. The outputs of this analysis directly drive security investment prioritization: components and functions assessed as most critical receive the most rigorous design-phase protections, supply chain scrutiny, and operational security controls, while lower-criticality elements are protected proportionately. Criticality analysis findings should inform the application of complementary security design principles, including network and functional segmentation and least-privilege access control, to isolate critical components from less-trusted system elements and reduce the consequence of compromise elsewhere in the system. Supply chain protection resources and oversight rigor should be explicitly allocated in proportion to component criticality, ensuring that the most mission-essential hardware and software receive the most intensive sourcing controls, provenance verification, and supplier oversight. Criticality analysis must be initiated early in the system design process and updated as the architecture evolves, threat intelligence changes, or operational experience reveals previously unrecognized dependencies. | CM-4 CP-2 CP-2(8) PL-7 PL-8 PL-8(1) PM-11 PM-17 PM-30 PM-30(1) PM-32 RA-3 RA-3(1) RA-9 SA-11 SA-11(3) SA-15(3) SA-2 SA-3 SA-4(5) SA-4(9) SA-8 SA-8(25) SA-8(3) SA-8(30) SC-32(1) SC-7(29) SR-1 SR-2 SR-2(1) SR-3 SR-3(2) SR-3(3) SR-5(1) SR-7 | A.8.9 7.5.1 7.5.2 7.5.3 A.5.2 A.5.29 A.8.1 A.5.30 8.1 A.5.8 A.5.8 4.4 6.2 7.5.1 7.5.2 7.5.3 10.2 6.1.2 8.2 9.3.2 A.8.8 A.5.22 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 A.8.29 A.8.30 5.2 5.3 7.5.1 7.5.2 7.5.3 A.5.1 A.5.2 A.5.4 A.5.19 A.5.31 A.5.36 A.5.37 A.5.19 A.5.20 A.5.21 A.8.30 A.5.20 A.5.21 A.5.22 | ||||
| CM0024 | Anti-counterfeit Hardware | Counterfeit electronic components represent a direct supply chain threat to space mission integrity, introducing hardware that may fail prematurely, perform outside specification, or contain malicious functionality deliberately embedded by an adversary during manufacture or distribution. A formal anti-counterfeit program must establish policy and procedures that span the entire component acquisition and integration lifecycle, from supplier qualification and procurement through incoming inspection, storage, and installation. The program must address two distinct but related risks: counterfeit components that fail to perform their intended function, degrading mission reliability; and deliberately tampered components that introduce malicious hardware functionality or create pathways for malicious code execution. Anti-counterfeit controls must include measures appropriate to component criticality and supply chain risk to authenticate components, detect evidence of tampering, and resist unauthorized modification. Detection and prevention must be treated as complementary objectives: prevention through qualified sourcing and procurement controls, detection through inspection and authentication techniques applied before components enter the system. | AC-14 AC-20(5) CM-7(9) PL-8 PL-8(1) PM-30 PM-30(1) RA-3(1) SA-10(3) SA-10(4) SA-11 SA-3 SA-4(5) SA-8 SA-8(11) SA-8(13) SA-8(16) SA-9 SR-1 SR-10 SR-11 SR-11(3) SR-2 SR-2(1) SR-3 SR-4 SR-4(1) SR-4(2) SR-4(3) SR-4(4) SR-5 SR-5(2) SR-6(1) SR-9 SR-9(1) | A.5.8 4.4 6.2 7.5.1 7.5.2 7.5.3 10.2 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 A.5.2 A.5.4 A.5.8 A.5.14 A.5.22 A.5.23 A.8.21 A.8.29 A.8.30 5.2 5.3 7.5.1 7.5.2 7.5.3 A.5.1 A.5.2 A.5.4 A.5.19 A.5.31 A.5.36 A.5.37 A.5.19 A.5.20 A.5.21 A.8.30 A.5.20 A.5.21 A.5.21 A.8.30 A.5.20 A.5.21 A.5.23 A.8.29 | ||||
| CM0025 | Supplier Review | A supplier review is a structured pre-contract assessment conducted before entering into any agreement with a contractor or subcontractor for the acquisition of systems, system components, or system services. The review evaluates the prospective supplier's security posture, trustworthiness, and capability to deliver components or services that meet the mission's integrity and assurance requirements, before contractual commitments are made and before the supplier gains access to mission information or influence over mission systems. Supplier reviews reduce the risk of introducing supply chain vulnerabilities through poorly qualified, compromised, or adversary-influenced suppliers at any tier of the acquisition chain. The rigor and depth of the review should be calibrated to the criticality of the components or services being acquired, with suppliers of mission-critical hardware, software, or services subject to the most intensive assessment. Supplier review findings should inform not only the decision to contract but also the specific security requirements, oversight provisions, and flow-down obligations included in the resulting agreement. | PL-8 PL-8(1) PL-8(2) PM-30 PM-30(1) RA-3(1) SA-11 SA-11(3) SA-17 SA-2 SA-3 SA-8 SA-9 SR-11 SR-3(1) SR-3(3) SR-4 SR-4(1) SR-4(2) SR-4(3) SR-4(4) SR-5 SR-5(1) SR-5(2) SR-6 | A.5.8 4.4 6.2 7.5.1 7.5.2 7.5.3 10.2 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 A.5.2 A.5.4 A.5.8 A.5.14 A.5.22 A.5.23 A.8.21 A.8.29 A.8.30 A.8.25 A.8.27 A.5.21 A.8.30 A.5.20 A.5.21 A.5.23 A.8.29 A.5.22 | ||||
| CM0028 | Tamper Protection | Tamper protection encompasses physical and logical controls that detect, deter, and respond to unauthorized modification of mission hardware and software throughout the acquisition, transit, storage, integration, and operational phases of the mission lifecycle. Physical tamper protection requires inspection of hardware at defined custody transfer points to detect evidence of unauthorized access or modification, and requires the use of tamper-evident packaging and sealing mechanisms during shipping and receiving to ensure that any interference with equipment in transit is detectable upon arrival. Logical tamper protection addresses the integrity of software and firmware through layered techniques including code obfuscation, integrity checks that verify software has not been altered from its approved state, and runtime integrity monitoring mechanisms such as self-checking code. Watchdog processes may supplement these controls by detecting abnormal execution or failure to complete expected processing, but do not by themselves verify software integrity. Physical and logical tamper protections are complementary and should be applied together where warranted by system criticality, threat exposure, and lifecycle conditions. Physical access to hardware can enable logical tampering, while failure to verify software integrity can reduce the assurance provided by physical controls. | AC-14 AC-25 CA-8(1) CA-8(3) CM-7(9) MA-7 PL-8 PL-8(1) PL-8(2) PM-30 PM-30(1) RA-3(1) SA-10(3) SA-10(4) SA-11 SA-3 SA-4(5) SA-4(9) SA-8 SA-8(11) SA-8(13) SA-8(16) SA-8(19) SA-8(31) SA-9 SC-51 SR-1 SR-10 SR-11 SR-11(3) SR-2 SR-2(1) SR-3 SR-4(3) SR-4(4) SR-5 SR-5(2) SR-6(1) SR-9 SR-9(1) | A.5.8 4.4 6.2 7.5.1 7.5.2 7.5.3 10.2 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 A.5.2 A.5.4 A.5.8 A.5.14 A.5.22 A.5.23 A.8.21 A.8.29 A.8.30 5.2 5.3 7.5.1 7.5.2 7.5.3 A.5.1 A.5.2 A.5.4 A.5.19 A.5.31 A.5.36 A.5.37 A.5.19 A.5.20 A.5.21 A.8.30 A.5.20 A.5.21 A.5.20 A.5.21 A.5.23 A.8.29 | ||||
| CM0040 | Shared Resource Leakage | Shared system resources (e.g., processor registers, main memory, secondary storage, cache) may retain residual data or security-relevant state after a process releases them for reuse. If a subsequent process can access that residual information, it may obtain data from the prior process, including sensitive information or encrypted representations of information that were not intended to cross process or partition boundaries. This countermeasure requires that shared resources be sanitized, zeroed, or otherwise cleared of prior process data before being allocated to a new process, ensuring that information transfer between processes occurs only through explicitly authorized channels. The protection must apply to encrypted representations as well as plaintext because encrypted data remains information belonging to the prior process and must not be transferred to another process solely because its contents are not immediately readable. This is particularly significant in space system environments where multiple processes of varying criticality and trust levels may share the same hardware resources. | AC-4(23) AC-4(25) SA-8(19) SA-8(2) SA-8(5) SA-8(6) SC-2(2) SC-3(4) SC-32(1) SC-4 SC-49 SC-50 SC-7(29) | A.8.11 A.8.10 | ||||
| CM0004 | Development Environment Security | A secure development environment requires a current and sufficiently complete inventory of the people, devices, software, services, credentials, and automated identities capable of accessing or influencing the environment. The development environment includes source-code repositories, developer workstations, build servers, CI/CD runners, compiler and linker toolchains, container and virtual machine images, package registries, artifact repositories, signing systems, test environments, integration laboratories, and release-staging systems. For space systems, these environments may produce or manage flight software images, firmware, FPGA bitstreams, software-defined radio waveforms, command and telemetry databases, configuration tables, ephemerides, calibration products, fault-management logic, and on-orbit update packages. Unmanaged assets, unauthorized access, compromised dependencies, altered toolchains, and untrusted build services are significant pathways through which adversaries may maliciously modify software or other mission artifacts during development and build activities. All personnel and assets touching the development environment must be inventoried and actively managed. MFA shall be enforced for human access, while non-human identities shall use managed workload identities, scoped credentials, protected secrets, and defined rotation or expiration period, with particular rigor applied to code repositories, where threat actors may attempt to inject malicious code into software under development without detection. Zero-trust access controls should govern repository access, with protected branch and tag policies shall restrict direct modification, prohibit unauthorized force pushes or deletion, require successful security checks, and require independent review before merging or releasing critical code. Effective development environment security also requires integrated change management, privilege management, comprehensive audit logging, and continuous in-depth monitoring across all components of the environment. | AC-17 AC-18 AC-20(5) AC-3(11) AC-3(13) AC-3(15) CA-8 CA-8(1) CM-11 CM-14 CM-2(2) CM-3(2) CM-3(7) CM-3(8) CM-4(1) CM-5(6) CM-7(8) CP-2(8) MA-7 PL-8 PL-8(1) PL-8(2) PM-30 PM-30(1) RA-3(1) RA-3(2) RA-5 RA-5(2) RA-9 SA-10 SA-10(4) SA-11 SA-11(1) SA-11(2) SA-11(4) SA-11(5) SA-11(6) SA-11(7) SA-11(8) SA-15 SA-15(3) SA-15(5) SA-15(7) SA-15(8) SA-17 SA-3 SA-3(1) SA-3(2) SA-4(12) SA-4(3) SA-4(5) SA-4(9) SA-8 SA-8(19) SA-8(30) SA-8(31) SA-9 SC-38 SI-2 SI-2(6) SI-7 SR-1 SR-11 SR-2 SR-2(1) SR-3 SR-3(2) SR-4 SR-4(1) SR-4(2) SR-4(3) SR-4(4) SR-5 SR-5(2) SR-6 SR-6(1) SR-7 | A.8.4 A.5.14 A.6.7 A.8.1 A.5.14 A.8.1 A.8.20 A.8.9 A.8.9 A.8.31 A.8.19 A.5.30 A.5.8 4.4 6.2 7.5.1 7.5.2 7.5.3 10.2 A.8.8 A.5.22 A.5.2 A.5.8 A.8.25 A.8.31 A.8.33 A.8.28 A.8.27 A.8.28 A.5.2 A.5.4 A.5.8 A.5.14 A.5.22 A.5.23 A.8.21 A.8.9 A.8.28 A.8.30 A.8.32 A.8.29 A.8.30 A.8.28 A.5.8 A.8.25 A.8.28 A.8.25 A.8.27 A.6.8 A.8.8 A.8.32 5.2 5.3 7.5.1 7.5.2 7.5.3 A.5.1 A.5.2 A.5.4 A.5.19 A.5.31 A.5.36 A.5.37 A.5.19 A.5.20 A.5.21 A.8.30 A.5.20 A.5.21 A.5.21 A.8.30 A.5.20 A.5.21 A.5.23 A.8.29 A.5.22 A.5.22 | ||||
| CM0039 | Least Privilege | The principle of least privilege requires that every process, user account, service, and system component be granted only the permissions and access rights necessary to perform its defined function, with no additional privileges retained beyond what the assigned task requires. Applied to spacecraft and ground systems, this means that processes executing on flight computers, operating system services, ground system applications, and inter-system communication handlers are each confined to the minimum privilege level needed for their specific function, preventing a compromised or malfunctioning component from leveraging excess permissions to affect other system resources or functions. Separate execution domains should be used where supported to reinforce least privilege and contain process failures or compromise. Process isolation does not replace explicit access controls, because authorized communication and shared resources may still cross execution-domain boundaries. Least privilege is a foundational design principle that reduces the consequence of any individual component compromise by limiting what an adversary can accomplish within that component's execution context. | AC-2 AC-3(13) AC-3(15) AC-4(2) AC-6 CA-3(6) CM-7 CM-7(5) CM-7(8) PL-8 PL-8(1) SA-17(7) SA-3 SA-4(9) SA-8 SA-8(13) SA-8(14) SA-8(15) SA-8(19) SA-8(3) SA-8(4) SA-8(9) SC-2(2) SC-32(1) SC-49 SC-50 SC-7(29) | A.5.16 A.5.18 A.8.2 A.5.15 A.8.2 A.8.18 A.8.19 A.8.19 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 | ||||
| CM0005 | Ground-based Countermeasures | Ground-based countermeasures protect the terrestrial capabilities that develop, launch, command, monitor, operate, secure, and sustain space missions. These capabilities may be distributed across mission-owned systems, contractor environments, external partners, and commercial service providers. Because ground segment architectures and responsibilities vary, cybersecurity protections should be selected through threat-informed analysis of the mission functions being performed rather than through indiscriminate application of a single control set. The SPARTA Ground Segment Cyber Defenses guidance provides an interactive functional decomposition that maps ground segment function groups to applicable Defense-in-Depth sub-layers and countermeasure targets. The supporting report, VTR-2026-00702 Rev A, Ground Segment Cyber Defenses and Risk-Based Tiering, provides the methodology, definitions, and risk-tier rationale. The accompanying Ground Segment Cyber Defenses Excel Workbook consolidates the function mappings and Baseline and Enhanced countermeasure guidance into a resource that can be tailored to a specific mission architecture. | SPARTA Ground Segment Cyber Defenses guidance | None | ||||
| CM0032 | On-board Intrusion Detection & Prevention | An on-board intrusion detection and prevention system (IDS/IPS) monitors mission-critical spacecraft components and systems, generates and stores audit records, and supports mission-approved responses to detected threats. Depending on the mission architecture, threat, and availability of ground support, responses may be autonomous, ground-directed, or a combination of both. The system should address both known attack patterns and previously unseen anomalous behavior through complementary signature-based and behavior- or anomaly-based detection methods. Machine learning or adaptive technologies may be used when their performance, resource consumption, and failure behavior have been validated for the mission environment. Detection and response coverage should address applicable adversary activities across the attack lifecycle, including initial access, execution, persistence, defense evasion, and exfiltration. The on-board IDS/IPS must be integrated with the spacecraft's traditional fault management system to provide a unified approach to anomaly response, ensuring that cyber-triggered responses are compatible with fault management logic and do not produce unintended effects or fratricide against the spacecraft's own systems; countermeasures that are incompatible with fault management are considered unsafe and must not be executed autonomously. The response hierarchy must prioritize vehicle safety and continued mission operations. Advanced containment or deception responses may be considered when they can be executed without unacceptable mission risk. The system should preserve evidence that supports post-event analysis, threat characterization, and potential attribution by authorized ground support. | AU-14 AU-2 AU-3 AU-3(1) AU-4 AU-4(1) AU-5 AU-5(2) AU-5(5) AU-6(1) AU-6(4) AU-8 AU-9 AU-9(2) AU-9(3) CA-7(6) CM-11(3) CP-10 CP-10(4) IR-4 IR-4(11) IR-4(12) IR-4(14) IR-4(5) IR-5 IR-5(1) PL-8 PL-8(1) RA-10 RA-3(4) SA-8(21) SA-8(22) SA-8(23) SC-16(2) SC-32(1) SC-5 SC-5(3) SC-7(10) SC-7(9) SI-10(6) SI-16 SI-17 SI-3 SI-3(10) SI-3(8) SI-4 SI-4(1) SI-4(10) SI-4(11) SI-4(13) SI-4(16) SI-4(17) SI-4(2) SI-4(23) SI-4(24) SI-4(25) SI-4(4) SI-4(5) SI-4(7) SI-6 SI-7(17) SI-7(8) | A.8.15 A.8.15 A.8.6 A.8.17 A.5.33 A.8.15 A.8.15 A.5.29 A.5.25 A.5.26 A.5.27 A.5.8 A.5.7 A.8.12 A.8.7 A.8.16 A.8.16 A.8.16 A.8.16 | ||||
| CM0067 | Smart Contracts | Smart contracts provide an automated, consensus-based enforcement mechanism for security protocols governing data exchange across a spacecraft bus, particularly in hosted payload architectures where multiple independently operated payloads or subsystems share common infrastructure. By encoding security rules as deterministic contract logic, participating validator nodes can evaluate authenticated observations of bus activity and reach consensus on whether a defined violation occurred. A trusted bus controller, gateway, or access-control mechanism must then enforce any approved restriction because the smart contract itself cannot directly observe or block physical bus traffic. This approach is directly applicable to scenarios where a hosted payload is compromised or behaves maliciously, as the smart contract framework can detect the violation, achieve consensus among the remaining bus participants, and enforce exclusion of the offending payload before the attack propagates to other bus components or the host spacecraft. The consensus mechanism should prevent a single participating node from causing payload exclusion when the approved quorum and membership rules require agreement from multiple independent validators. Its effectiveness depends on the validator architecture, quorum threshold, communication assumptions, and number of compromised or unavailable validators. Smart contract-based enforcement is particularly valuable in multi-tenant spacecraft architectures where payload operators are organizationally distinct from the spacecraft bus operator and cannot be governed through a single chain of administrative control. | IA-9 SI-4 SI-4(2) | A.8.16 | ||||
| CM0038 | Segmentation | Segmentation establishes physical or logical isolation boundaries between spacecraft system components and functional domains to limit the propagation of compromise, contain the consequences of a security failure, and enforce controlled information flow across the mission architecture. Mission-critical functions must be isolated from non-mission-critical functions through enforced partition boundaries that control access to and protect the integrity of the hardware, software, and firmware implementing those functions. Information flow between partitioned components or applications must be explicitly authorized by security policy; any flow not affirmatively permitted is denied by default. Boundary protections must be implemented to separate spacecraft bus, communications, and payload components, preventing a compromise in one domain from directly affecting the others. Information crossing the spacecraft boundary shall receive confidentiality protection where required by its classification, sensitivity, or mission risk. Command-bearing and other security-critical exchanges shall receive the mission-required authentication, integrity, authorization, and anti-replay protections regardless of whether confidentiality is required. These controls collectively implement a defense-in-depth architecture in which an adversary who gains a foothold in one partition faces enforced barriers before reaching mission-critical assets. | AC-4 AC-4(14) AC-4(2) AC-4(24) AC-4(26) AC-4(31) AC-4(32) AC-4(6) AC-6 CA-3 CA-3(7) PL-8 PL-8(1) SA-3 SA-8 SA-8(13) SA-8(15) SA-8(18) SA-8(3) SA-8(4) SA-8(9) SC-16(3) SC-2(2) SC-3 SC-3(4) SC-32 SC-32(1) SC-39 SC-4 SC-49 SC-50 SC-6 SC-7(20) SC-7(21) SC-7(29) SC-7(5) SI-17 SI-4(7) | A.5.14 A.8.22 A.8.23 A.5.15 A.8.2 A.8.18 A.5.14 A.8.21 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 | ||||