Three main parts of S/C. CPU, memory, I/O interfaces with parallel and/or serial ports. These are connected via busses (i.e., 1553) and need segregated. Supply chain attack on CPU (FPGA/ASICs), supply chain attack to get malware burned into memory through the development process, and rogue RTs on 1553 bus via hosted payloads are all threats. Security or fault management being disabled by non-mission critical or payload; fault injection or MiTM into the 1553 Bus - China has developed fault injector for 1553 - this could be a hosted payload attack if payload has access to main 1553 bus; One piece of FSW affecting another. Things are not containerized from the OS or FSW perspective;
| SPARTA ID | Requirement | Rationale/Additional Guidance/Notes |
|---|---|---|
| SPR-3 | The [spacecraft] shall enforce approved authorizations for controlling the flow of information within the platform and between interconnected systems so that information does not leave the platform boundary unless it is encrypted. Flow control shall be implemented in conjunction with protected processing domains, security‑policy filters with fully enumerated formats, and a default‑deny communications baseline.{SV-AC-6}{AC-3(3),AC-3(4),AC-4,AC-4(2),AC-4(6),AC-4(21),CA-3,CA-3(6),CA-3(7),CA-9,IA-9,SA-8(19),SC-8(1),SC-16(3)} | Spacecraft operate in constrained and deterministic environments where uncontrolled data flows can enable data exfiltration, cross-domain leakage, or lateral movement between subsystems. Enforcing approved authorizations with enumerated formats and a default-deny posture ensures only explicitly permitted communications occur. Encryption enforcement at platform boundaries prevents unauthorized disclosure of telemetry or state information. |
| SPR-4 | The [spacecraft] security implementation shall ensure that information should not be allowed to flow between partitioned applications unless explicitly permitted by the system.{SV-AC-6,SV-MA-3,SV-SP-7}{AC-3(3),AC-3(4),AC-4,AC-4(6),AC-4(21),CA-9,IA-9,SA-8(3),SA-8(18),SA-8(19),SC-2(2),SC-7(29),SC-16,SC-32} | Strict partitioning prevents compromise of one application from cascading into mission-critical subsystems. Many spacecraft attacks exploit flat architectures where subsystems implicitly trust one another. Explicit inter-partition authorization limits lateral movement and privilege escalation. This supports containment and fault isolation under both cyber and fault conditions. |
| SPR-5 | The [organization] shall state that information should not be allowed to flow between partitioned applications unless explicitly permitted by the Program's security policy.{SV-AC-6}{AC-4,AC-4(6)} | Technical enforcement must be anchored in formal policy to ensure consistency across development, integration, and operations. Codifying partition isolation requirements prevents mission creep and ad hoc exceptions that weaken domain separation. This establishes traceability between architecture design and security governance. It also ensures subcontractors and integrators apply consistent constraints. |
| SPR-16 | The [spacecraft] shall ensure that processes reusing a shared system resource (e.g., registers, main memory, secondary storage) do not have access to information (including encrypted representations of information) previously stored in that resource after formal release, by clearing or zeroizing the resource prior to reuse.{SV-AC-6}{AC-3,PM-32,SA-8(2),SA-8(5),SA-8(6),SA-8(19),SC-4,SI-3} | Residual data in memory or registers can create covert channels or leakage paths between partitions. Zeroization prevents recovery of sensitive data by subsequent processes. This mitigates cross-domain leakage and memory scraping attacks. Clearing encrypted remnants is equally important to prevent cryptanalytic exploitation. |
| SPR-21 | The [spacecraft], when transferring information between different security domains, shall implement security‑policy filters that require fully enumerated formats that restrict data structure and content.{SV-AC-6}{AC-3(3),AC-3(4),AC-4(14),IA-9,SA-8(19),SC-16,SI-10} | Fully enumerated formats prevent injection of malformed or malicious data across security domains. This reduces parser exploitation, data smuggling, and covert channel abuse. Strict domain filtering supports deterministic and auditable inter-domain communication. Only explicitly defined data structures should be permitted. |
| SPR-22 | The [spacecraft] shall implement boundary protections to separate bus, communications, and payload components supporting their respective functions.{SV-AC-6}{AC-3(3),AC-3(4),CA-9,SA-8(3),SA-8(14),SA-8(18),SA-8(19),SA-17(7),SC-2,SC-2(2),SC-7(13),SC-7(21),SC-7(29),SC-16(3),SC-32,SI-3,SI-4(13),SI-4(25)} | Flat architectures allow compromise of one subsystem to impact all others. Segregated boundaries reduce lateral movement and mission degradation. Isolation ensures payload compromise does not impact TT&C or bus control. This supports containment and survivability. |
| SPR-23 | The [spacecraft] shall isolate mission critical functionality from non-mission critical functionality.{SV-AC-6}{AC-3(3),AC-3(4),CA-9,SA-8(3),SA-8(19),SA-17(7),SC-2,SC-3,SC-3(4),SC-7(13),SC-7(29),SC-32,SC-32(1),SI-3,SI-7(10),SI-7(12)} | Non-critical functions often expand attack surface. Isolation prevents less-trusted components from affecting propulsion, attitude control, or power systems. This reduces cascading failure risk under compromise. Mission-critical systems must maintain operational continuity. |
| SPR-24 | The [spacecraft] data within partitioned applications shall not be read or modified by other applications/partitions.{SV-AC-6}{AC-3(3),AC-3(4),SA-8(19),SC-2(2),SC-4,SC-6,SC-32} | Application partitions must enforce strict read/write controls to prevent unauthorized state modification. Without this control, malicious code can alter mission parameters or falsify telemetry. Isolation protects integrity of subsystem data and prevents corruption propagation. |
| SPR-25 | The [spacecraft] shall prevent unauthorized access to system resources by employing an efficient capability based object model that supports both confinement and revocation of these capabilities when the platform security deems it necessary.{SV-AC-6}{AC-3(8),IA-4(9),PM-32,SA-8(2),SA-8(5),SA-8(6),SA-8(18),SA-8(19),SC-2(2),SC-4,SC-16,SC-32,SI-3} | Capability models restrict access to explicit, revocable tokens of authority. This enforces least privilege and supports dynamic revocation under threat conditions. Confinement reduces damage radius of compromised processes. Revocation capability enables adaptive cyber response. |
| SPR-26 | The [spacecraft] shall use protected processing domains to enforce the policy that information does not leave the platform boundary unless it is encrypted as a basis for flow‑control decisions and shall enumerate permitted inter‑domain flows and enforce domain‑gate checks on any domain switch. {SV-AC-6}{AC-4(2),IA-9,SA-8(19),SC-8(1),SC-16(3)} | Domain gates provide controlled transition points between security domains. Enumerated flows prevent unintentional data leakage and enforce encryption policies at boundaries. This mitigates cross-domain injection and exfiltration. Strong gate enforcement prevents privilege escalation during context switching. |
| SPR-39 | The [spacecraft] shall prevent unauthorized and unintended information transfer via shared system resources.{SV-AC-6}{PM-32,SA-8(2),SA-8(5),SA-8(6),SA-8(19),SC-2(2),SC-4} | Shared buses, memory, or peripherals can become covert channels. Controls must prevent unintended information propagation across shared infrastructure. This mitigates cross-partition leakage and data exfiltration. Shared resources must not undermine domain isolation. |
| SPR-41 | The [spacecraft] shall maintain a separate execution domain for each executing process.{SV-AC-6}{SA-8(14),SA-8(19),SC-2(2),SC-7(21),SC-39,SI-3} | Process isolation prevents one compromised task from impacting others. Separate execution domains mitigate memory corruption and privilege escalation. This strengthens containment of malicious code. Deterministic isolation enhances both safety and cybersecurity. |
| SPR-42 | The [spacecraft] flight software shall not be able to tamper with the security policy or its enforcement mechanisms.{SV-AC-6}{SA-8(16),SA-8(19),SC-3,SC-7(13)} | Security enforcement must be independent of mission application logic. If FSW can alter policy, adversaries can disable protections post-compromise. This control preserves integrity of access controls and monitoring functions. Separation of enforcement from application reduces systemic risk. |
| SPR-77 | The [spacecraft] shall employ the principle of least privilege, allowing only authorized accesses processes which are necessary to accomplish assigned tasks in accordance with system functions.{SV-AC-6}{AC-3,AC-6,AC-6(9),CA-9,CM-5,CM-5(5),CM-5(6),SA-8(2),SA-8(5),SA-8(6),SA-8(14),SA-8(23),SA-17(7),SC-2,SC-7(29),SC-32,SC-32(1),SI-3} | Least privilege limits damage from compromised processes or insider misuse. Processes receive only the minimum access necessary for assigned functions. This reduces lateral movement and privilege escalation pathways. In deterministic spacecraft systems, privilege boundaries must be tightly defined and enforced. |
| SPR-78 | The [spacecraft] shall provide independent mission/cyber critical threads such that any one credible event will not corrupt another mission/cyber critical thread.{SV-AC-6,SV-MA-3,SV-SP-7}{SC-3,SC-32,SC-32(1),SI-3,SI-13} | Segregating mission-critical and cyber-critical execution paths prevents a single failure or compromise from corrupting other critical functions. Thread independence supports fault containment and resilience under attack. This ensures availability of essential functions even during partial compromise. Isolation strengthens both safety and cybersecurity. |
| SPR-108 | The [organization] shall define the resources to be allocated to protect the availability of system resources.{SV-AC-6}{CP-2(2),SC-6} | Availability protections require deliberate allocation of compute, power, bandwidth, and monitoring capacity. Without predefined resource allocation, defensive measures may compete with mission operations. Planning ensures resilience mechanisms do not degrade core functionality. This supports continuity during denial-of-service conditions. |
| SPR-163 | The [spacecraft] shall employ monitoring mechanisms to detect and respond to unauthorized or excessive use of external systems, safeguarding the organization's information and ensuring the integrity, confidentiality, and availability of its resources.Monitoring shall be performed on crosslink communications as well as space to ground communications (including direct to user tactical downlinks such as utilized in real-time imagery acquisition).{SV-AC-6,SV-DCO-1,SV-CF-1}{AC-20,AC-20(1)} | Monitoring detects anomalous bandwidth use, potential exfiltration, or misuse. Crosslinks are lateral movement pathways between spacecraft. Oversight protects enterprise integrity. Visibility supports coordinated response. |
| SPR-176 | The [spacecraft] shall establish, manage, and monitor internal connections between system components in accordance with organization-defined security policies and procedures.{SV-AC-6,SV-MA-3}{CA-9} | Internal connections for spacecraft may include certain subsystems and payloads that communicate across a common bus. |
| SPR-194 | The [spacecraft] shall physically isolate security tools, mechanisms, and support components used for boundary protection within the spacecraft.{SV-AC-6,SV-MA-3}{SC-7(13)} | Boundary protection mechanisms must be protected from tampering. Physical isolation reduces risk of compromise via shared buses or payload interfaces. Defensive systems require integrity to remain trustworthy. Separation reinforces defense-in-depth. |
| SPR-202 | The [organization] shall define the security safeguards to be employed to protect the availability of system resources.{SV-AC-6}{SC-6,SI-17} | Explicit availability planning ensures defensive resources are provisioned. Clear safeguards prevent ad hoc reactions during incidents. Structured resilience planning supports mission assurance. Availability is often a primary operational objective. |
| SPR-212 | The [spacecraft] shall be capable of shutting off specific subsystems or payloads to isolate malicious activity or protect the platform.{SV-MA-3,SV-AC-6,SV-SP-3,SV-MA-8}{PE-10} | Isolation limits impact of compromised components. Segmentation prevents systemic compromise. Controlled shutdown preserves overall platform health. Modular containment strengthens survivability. |
| SPR-225 | The [spacecraft] shall protect the availability of resources by allocating [organization]-defined resources based on [priority and/or quota].{SV-AC-6}{SC-6} | In particular, this control is required for all space platform buses to ensure execution of high priority functions; it is particularly important when there are multiple payloads sharing a bus providing communications and other services, where bus resources must be prioritized based on mission. |
| SPR-226 | The [spacecraft] shall implement dynamic isolation and segregation mechanisms for boundary protection to enhance its security by isolating components when necessary (e.g.compromised/malicious payload).{SV-AC-6,SV-MA-3}{SC-7(20)} | Ability to isolate compromised components reduces lateral spread. Dynamic segmentation enhances resilience in active attack scenarios. Isolation supports autonomous containment. Modular protection improves survivability. |
| SPR-309 | The [organization] shall identify the key system components or capabilities that require isolation through physical or logical means.{SV-AC-6}{AC-3,SC-3,SC-7(13),SC-28(3),SC-32,SC-32(1)} | Fault management and security management capabilities would be classified as mission critical and likely need separated. Additionally, capabilities like TT&C, C&DH, GNC might need separated as well. |
| SPR-458 | The [spacecraft] shall enforce [organization]-defined domain based routing policies that restrict which subsystems may relay information to one another.{SV-AC-6}{CA-3(7),AC-4} | Domain segmentation prevents unrestricted lateral data movement. Restricting which subsystems may relay information reduces cross-domain compromise risk. Routing policy enforcement supports least privilege and mission isolation. Structured boundaries strengthen resilience. |
| SPR-486 | The [spacecraft] shall structure security-relevant software and firmware into cohesive modules that expose only [organization]-approved interfaces and prevent unintended cross-module data or control flow. {SV-AC-6}{SC-3,SC-3(4)} | Cohesive modules reduce unintended coupling. Limited interfaces prevent cross-module exploitation. Clear boundaries strengthen isolation. Structured architecture supports resilience. |
| SPR-487 | The [spacecraft] shall verify during integration that modules providing security functions are isolated from non-security modules and that dependencies are limited to documented interfaces.{SV-AC-6}{SC-3,SC-3(4)} | Integration validation ensures isolation is effective. Limiting dependencies reduces lateral risk. Structured interface enforcement strengthens policy assurance. Verification prevents silent drift. |
| SPR-489 | The [spacecraft] shall host privileged functions, including flight control and cryptographic key management, in physically separate processing domains that have no direct data bus connectivity to non privileged domains. {SV-AC-6,SV-AC-3}{SC-3,SC-32(1),SC-39} | Hardware-level separation prevents software bypass. Isolation protects flight control and key management. Physical boundaries strengthen trust. Segmentation enforces zero-trust architecture. |
| SPR-490 | The [spacecraft] shall ensure cross domain exchanges occur only through [organization] defined, verified guards that enforce format, rate, and content checks.{SV-AC-6,SV-IT-2}{AC-4,SC-7,SC-32(1)} | Verified guards ensure controlled data exchange. Format and rate checks prevent covert channel exploitation. Enforced mediation supports mandatory control. Guarded exchange strengthens isolation. |
| ID | Name | Description | |
|---|---|---|---|
| IA-0005 | Rendezvous & Proximity Operations | Adversaries may execute a sequence of orbital maneuvers to co-orbit and approach a target closely enough for local sensing, signaling, or physical interaction. Proximity yields advantages that are difficult to achieve from Earth: high signal-to-noise for interception, narrowly targeted interference or spoofing, observation of attitude/thermal behavior, and, if interfaces exist, opportunities for mechanical mating. The approach typically unfolds through phasing, far-field rendezvous, relative navigation (e.g., vision, lidar, crosslink cues), and closed-loop final approach. At close distances, an attacker can monitor side channels, stimulate acquisition beacons, test crosslinks, or prepare for contact operations such as capture or docking. Contact itself is not the endpoint: mating and grappling expose data and power umbilicals, standardized payload ports, service and checkout connectors, and device programming interfaces that are unreachable by any other means. | |
| IA-0005.02 | Docked Vehicle / OSAM | Docking, berthing, or service capture during on-orbit servicing, assembly, and manufacturing (OSAM) creates a high-trust bridge between vehicles. Threat actors exploit this moment, either by pre-positioning code on a servicing vehicle or by manipulating ground updates to it, so that, once docked, lateral movement occurs across the mechanical/electrical interface. Interfaces may expose power and data umbilicals, standardized payload ports, or gateways into the target’s C&DH or payload networks (e.g., SpaceWire, Ethernet, 1553). Service tools that push firmware, load tables, transfer files, or share time/ephemeris become conduits for staged procedures or implants that execute under maintenance authority. Malware can be timed to activation triggers such as “link up,” “maintenance mode entered,” or specific device enumerations that only appear when docked. Because OSAM operations are scheduled and well-documented, the adversary can align preparation with published timelines, ensuring that the first point of execution coincides with the brief window when cross-vehicle trust is intentionally elevated. | |
| IA-0013 | Compromise Host Spacecraft | The inverse of "IA-0006: Compromise Hosted Payload", this technique describes adversaries that are targeting a hosted payload, the host space vehicle (SV) can serve as an initial access vector to compromise the payload through vulnerabilities in the SV's onboard systems, communication interfaces, or software. If the SV's command and control systems are exploited, an attacker could gain unauthorized access to the vehicle's internal network. Once inside, the attacker may laterally move to the hosted payload, particularly if it shares data buses, processors, or communication links with the vehicle. | |
| EX-0001 | Replay | Replay is the re-transmission of previously captured traffic, over RF links, crosslinks, or internal buses, to elicit the same processing and effects a second time. Adversaries first observe and record authentic exchanges (telecommands, ranging/acquisition frames, housekeeping telemetry acknowledgments, bus messages), then resend them within acceptance conditions that the system recognizes, matching link geometry, timetags, counters, or mode states. The aim can be functional (re-triggering an action such as a mode change), observational (fingerprinting how the vehicle reacts at different states), or disruptive (saturating queues and bandwidth to crowd out legitimate traffic). Because replays preserve valid syntax and often valid context, they can blend with normal operations, especially during periods with reduced monitoring or when counters and windows reset (e.g., handovers, safing entries). On encrypted links, metadata replays (acquisition beacons, schedule requests) may still yield informative responses. | |
| EX-0001.02 | Bus Traffic Replay | Instead of the RF path, the attacker targets internal command/data handling by injecting or retransmitting messages on the spacecraft bus (e.g., 1553, SpaceWire, custom). Because many subsystems act on the latest message or on message rate rather than on uniqueness, a flood of historical yet well-formed frames can consume bandwidth, starve critical publishers, or cause subsystems to perform the same action repeatedly. Secondary effects include stale sensor values being re-consumed, watchdog timers being reset at incorrect intervals, and autonomy rules misclassifying the situation due to out-of-order but valid-looking events. On time-triggered or scheduled buses, replaying at precise offsets can collide with or supersede legitimate messages, steering system state without changing software. The goal is to harness the bus’s determinism, repeating prior internal stimuli to recreate prior effects or to induce resource exhaustion. | |
| LM-0001 | Hosted Payload | The adversary pivots through the host–payload boundary to reach additional subsystems. Hosted payloads exchange power, time, housekeeping, and data with the bus via defined gateways (e.g., SpaceWire, 1553, Ethernet) and often support file services, table loads, and command dictionaries distinct from the host’s. A foothold on the payload can be used to inject traffic through the gateway processor, request privileged services (time/ephemeris distribution, firmware loads), or ride shared backplanes where payload traffic is bridged into C&DH networks. In some designs, payload processes execute on host compute or expose maintenance modes that temporarily widen access, creating paths from the payload into attitude, power, storage, or recorder resources. The movement is transitive: compromise a co-resident unit, then traverse the trusted interface that already exists for mission operations. | |
| LM-0002 | Exploit Lack of Bus Segregation | On flat architectures, where remote terminals, subsystems, and payloads share a common bus with minimal partitioning, any node that can transmit may influence many others. An attacker leverages this by forging message IDs or terminal addresses, replaying actuator/sensor frames, seizing or imitating bus-controller roles, or abusing gateway bridges that forward traffic between links (e.g., 1553↔SpaceWire/CAN). Because consumers often act on the latest valid-looking message, crafted traffic from one compromised device can reconfigure peers, toggle power domains, or write persistent parameters. Weak role enforcement and broadcast semantics allow privilege escalation from a peripheral to effective system-wide influence, turning the shared medium into a highway for further compromise. | |
| ID | Name | Description | NIST Rev5 | D3FEND | ISO 27001 | |
|---|---|---|---|---|---|---|
| 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 | D3-AVE D3-OSM D3-IDA D3-SJA D3-AI D3-DI D3-SWI D3-NNI D3-HCI D3-NM D3-PLM D3-AM D3-SYSM D3-SVCDM D3-SYSDM D3-SYSVA D3-OAM D3-ORA | 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) | D3-AI D3-SWI D3-HCI D3-FEMC D3-DLIC D3-FV | 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 | D3-OAM D3-ODM | 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) | D3-PH D3-AH D3-RFS D3-FV | 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 | |
| CM0031 | Authentication | All command-bearing sessions, frames, or messages involving spacecraft command links, crosslinks, or relay services shall provide cryptographic authentication of the command origin and integrity verification before commands are accepted. Mutual or bidirectional authentication shall be required where both endpoints must authenticate one another and the link and protocol architecture support that exchange. Acquisition requirements should mandate cryptographically based, bidirectional authentication for all command sessions across external links, including ground-to-spacecraft uplinks, spacecraft-to-spacecraft crosslinks, and any relay or intermediary ground station connections, with authentication required aBidirectional authentication enables both communicating entities to verify each other’s identity and helps prevent impersonation. Authentication establishes identity but does not by itself authorize a command, protect mission-data confidentiality, or prevent session hijacking. Command acceptance must also enforce authorization, and authenticated sessions or security associations must maintain integrity and replay resistance so that subsequent traffic remains bound to the authenticated entities. Beyond external links, authentication is strongly recommended for spacecraft internal bus communications and onboard inter-component connections, as an adversary with access to internal interfaces, whether through a compromised component or a physical access event, should face the same authentication barrier as an external adversary attempting to inject commands from outside the spacecraft. | AC-14 AC-17 AC-17(10) AC-17(2) AC-18 AC-18(1) IA-2 IA-3(1) IA-4 IA-4(9) IA-7 IA-9 PL-8 PL-8(1) SA-3 SA-4(5) SA-8 SA-8(15) SA-8(9) SC-16 SC-16(1) SC-16(2) SC-32(1) SC-7(11) SC-8(1) SI-14(3) SI-7(6) | D3-MH D3-MAN D3-CH D3-BAN D3-MFA D3-TAAN D3-CBAN | A.5.14 A.6.7 A.8.1 A.5.14 A.8.1 A.8.20 A.5.16 A.5.16 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 A.5.33 | |
| 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) | D3-MAC D3-PAN D3-HBPI | A.8.11 A.8.10 | |
| CM0050 | On-board Message Encryption | Authentication controls on the spacecraft internal bus verify the identity of communicating components but do not protect the confidentiality of the data in transit; an adversary with access to the bus, whether through a compromised component, a hardware implant, or a physical access event, can observe all unencrypted inter-component communications regardless of whether authentication is enforced. Encrypting data traversing the spacecraft internal bus protects the confidentiality of selected message content from entities that can observe the bus but do not possess authorization and the applicable cryptographic keys. The protection does not prevent disclosure to a compromised component that legitimately possesses the decryption key, and it may not conceal unencrypted protocol headers, addressing information, message timing, or traffic volume. Bus encryption should be considered for bus segments or message types carrying information whose unauthorized disclosure would create unacceptable mission, security, privacy, or operational risk. Criticality alone does not establish a confidentiality requirement. Where confidentiality is required, encryption must be combined with message integrity, source authentication, and replay protection through an approved authenticated-encryption mechanism or an appropriately composed set of cryptographic protections. | AC-4 AC-4(23) AC-4(24) AC-4(26) AC-4(31) AC-4(32) PL-8 PL-8(1) SA-3 SA-8 SA-8(18) SA-8(19) SA-8(9) SA-9(6) SC-13 SC-16 SC-16(1) SC-16(2) SC-16(3) SC-8(1) SC-8(3) SI-19(4) SI-4(10) SI-4(25) | D3-MH D3-MENCR D3-ET | A.5.14 A.8.22 A.8.23 A.8.11 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 A.5.33 A.8.24 A.8.26 A.5.31 A.8.11 | |
| 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) | D3-MAC D3-EI D3-HBPI D3-KBPI D3-PSEP D3-MBT D3-PCSV D3-LFP D3-UBA | 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 | |
| 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) | D3-FA D3-DA D3-FCR D3-FH D3-ID D3-IRA D3-HD D3-IAA D3-FHRA D3-NTA D3-PMAD D3-RTSD D3-ANAA D3-CA D3-CSPP D3-ISVA D3-PM D3-SDM D3-SFA D3-SFV D3-SICA D3-USICA D3-FBA D3-FEMC D3-FV D3-OSM D3-PFV D3-EHB D3-IDA D3-MBT D3-SBV D3-PA D3-PSMD D3-PSA D3-SEA D3-SSC D3-SCA D3-FAPA D3-IBCA D3-PCSV D3-FCA D3-PLA D3-UBA D3-RAPA D3-SDA D3-UDTA D3-UGLPA D3-ANET D3-AZET D3-JFAPA D3-LAM D3-NI D3-RRID D3-NTF D3-ITF D3-OTF D3-EI D3-EAL D3-EDL D3-HBPI D3-IOPR D3-KBPI D3-MAC D3-SCF | 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) | D3-AM D3-PH D3-LFP D3-SCP | A.8.16 | |
| CM0037 | Disable Physical Ports | Physical data connection, debug, programming, and maintenance interfaces (e.g., joint test action group (JTAG)) that are not required for spacecraft operations must be disabled, removed, or otherwise made inaccessible before spacecraft operations begin. Interfaces required for operational functions must be explicitly identified and protected against unauthorized physical access and use. These interfaces, essential during development for programming, debugging, and testing, represent persistent attack surfaces in the operational environment: an adversary with physical access to the spacecraft before launch, during ground handling, or at a shared launch facility could exploit active debug interfaces to read memory, modify firmware, bypass security controls, or implant persistent malicious code without leaving detectable traces in software-visible logs. Disabling or removing unused physical interfaces closes a direct hardware-access pathway and reduces reliance on procedural controls or physical security alone. The capability to disable these interfaces must be designed into the system from the outset, as physical removal or reliable hardware-enforced disablement cannot be easily retrofitted into a completed board design. | AC-14 MA-7 PL-8 PL-8(1) SA-3 SA-4(5) SA-4(9) SA-8 SC-41 SC-7(14) | D3-EI D3-IOPR | A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28 | |
| 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) | D3-NI D3-BDI D3-NTF D3-ITF D3-OTF D3-EI D3-HBPI D3-KBPI D3-MAC D3-RRID D3-EAL D3-EDL D3-IOPR D3-SCF | 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 | |
| CM0065 | OSAM Dual Authorization | Before a cooperative OSAM engagement enters a protected proximity, capture, docking, mating, or servicing phase, the servicing spacecraft must be authenticated and the specific engagement authorized by both the serviced asset’s mission control authority and, where technically capable, the serviced asset itself. Authentication establishes the identity of the servicer, while dual authorization requires two independent approval decisions for the proposed activity. The approvals may be sequential rather than simultaneous but must both remain valid and be bound to the same servicer, client, service scope, mission phase, interfaces, operational constraints, and validity period. Failure to obtain or maintain authorization must cause the serviced asset to withhold cooperation and interface enablement and must invoke the approved hold, retreat, or abort response. These controls reduce the risk of unauthorized servicing but cannot physically prevent a hostile or non-cooperative spacecraft from approaching the asset. | CA-3(6) IA-2(1) IA-2(2) IA-2(6) | D3-OAM D3-AM D3-ODM D3-OM D3-MFA | None | |
| CM0071 | Communication Physical Medium | The physical medium selected for ground segment networking directly affects the mission's vulnerability to passive interception, traffic flow analysis, and electromagnetic eavesdropping, making medium selection a security design decision that must be informed by the mission's threat model. Fiber optic cabling transmits data optically and does not produce the same conducted or radiated electrical emanations as copper cabling, reducing exposure to proximity-based electromagnetic collection. Fiber may still be intercepted through physical access, optical coupling, compromised patch points, or endpoint equipment, and medium selection alone does not conceal traffic timing or volume from an observer with access to the link or its endpoints. Fiber should therefore be considered where the threat model identifies electromagnetic emanation or physical-medium interception risk, while cryptographic and physical protections remain applicable, particularly for links carrying mission-sensitive data such as command uplink traffic, cryptographic key material, or mission planning data. The selection of physical medium should be treated as a threat-informed engineering decision evaluated for each network segment based on the sensitivity of the data carried, the physical accessibility of the cabling, and the threat environment of the facility in which the cabling is installed. | PE-4 SC-8 SC-8(1) SC-8(3) SC-8(5) | D3-MH D3-PLM | A.7.2 A.7.12 A.5.10 A.5.14 A.8.20 A.8.26 A.5.33 | |