Backdoor Commands

Ensure that all viable commands are known to the mission/spacecraft owner. Perform analysis of critical (backdoor/hardware) commands that could adversely affect mission success if used maliciously. Only use or include critical commands for the purpose of providing emergency access where commanding authority is appropriately restricted.

NIST Rev5 Controls

D3FEND Techniques

D3FEND Artifacts

ISO 27001

NASA Best Practice Guide

ESA Space Shield Mitigation

None

Related MITRE EMB3D Mitigations

Related CSF 2.0

Related BSI Security Measures

No related BSI Security Measures

ID: CM0043

Tier: I

Onboard SV CM

Created: 2022/10/19

Last Modified: 2023/10/17

Techniques Addressed by Countermeasure

ID		Name	Description
EX-0006		Disable/Bypass Encryption	The adversary alters how confidentiality or integrity is applied so traffic or data is processed in clear or with weakened protection. Paths include toggling configuration flags that place links or storage into maintenance/test modes; forcing algorithm “fallbacks” or null ciphers; downgrading negotiated suites or keys; manipulating anti-replay/counter state so checks are skipped; substituting crypto libraries or tables during boot/update; and selecting alternate routes that carry the same content without encryption. On some designs, distinct modes handle authentication and confidentiality separately, allowing an actor who obtains authentication material to request unencrypted service or to switch to legacy profiles. The end state is that command, telemetry, or data products traverse a path the spacecraft accepts while cryptographic protection is absent, weakened, or inconsistently applied, enabling subsequent tactics such as inspection, manipulation, or exfiltration.
PER-0002		Backdoor	A backdoor is a covert access path that bypasses normal authentication, authorization, or operational checks so the attacker can reenter the system on demand. Backdoors may be preexisting (undocumented service modes, maintenance accounts, debug features) or introduced by the adversary during development, integration, or on-orbit updates. Triggers range from “magic” opcodes and timetags to specific geometry/time conditions, counters, or data patterns embedded in routine traffic. The access they provide varies from expanded command sets and relaxed rate/size limits to alternate communications profiles and hidden file/parameter interfaces. Well-crafted backdoors blend with nominal behavior, appearing as ordinary operations while quietly accepting instructions that other paths would reject, thereby sustaining the attacker’s foothold across passes, resets, and operator handovers.
	.01	Hardware Backdoor	Hardware backdoors leverage properties of the physical design to provide durable, low-visibility reentry. Examples include enabled test/scan chains, manufacturing or boot-strap modes invoked by pins or registers, persistent debug interfaces (JTAG/SWD/UART), undocumented device commands, and logic inserted in FPGA/ASIC designs that activates under specific stimuli. Because these mechanisms sit below or beside flight software, they can grant direct access to buses, memories, or peripheral control even when higher layers appear healthy. Triggers may be electrical (pin states, voltage/clock sequences), protocol-level (special patterns on an instrument link), or environmental/temporal (particular temperature ranges, timing offsets). Once on orbit, such pathways are difficult to remove or reconfigure, allowing the attacker to persist by reusing the same physical entry points whenever conditions are met.
	.02	Software Backdoor	Software backdoors are code paths intentionally crafted or later inserted to provide privileged functionality on cue. In flight contexts, they appear as hidden command handlers, alternate authentication checks, special user/role constructs, or procedure/script hooks that accept nonpublic inputs. They can be embedded in flight applications, separation kernels or drivers, gateway processors that translate bus/payload traffic, or update/loader utilities that handle tables and images. SDR configurations offer another avenue: non-public waveforms, subcarriers, or framing profiles that, when selected, expose a private command channel. Activation is often conditional, specific timetags, geometry, message sequences, or file names, to keep the feature dormant during routine testing and operations. Once present, the backdoor provides a repeatable way to execute commands or modify state without traversing the standard control surfaces, sustaining the adversary’s access over time.

Space Threats Addressed by Countermeasure

ID	Description
SV-AC-3	Compromised master keys or any encryption key
SV-AC-8	Malicious Use of hardware commands - backdoors / critical commands
SV-AV-5	Using fault management system against you. Understanding the fault response could be leveraged to get satellite in vulnerable state. Example, safe mode with crypto bypass, orbit correction maneuvers, affecting integrity of TLM to cause action from ground, or some sort of RPO to cause S/C to go into safe mode;

Sample Requirements

SPARTA ID	Requirement	Rationale/Additional Guidance/Notes
SPR-9	The [organization] shall implement a security architecture and design that provides the required security functionality, allocates security controls among physical and logical components, and integrates individual security functions, mechanisms, and processes together to provide required security capabilities and a unified approach to protection.{SV-MA-6}{PL-7,SA-2,SA-8,SA-8(1),SA-8(2),SA-8(3),SA-8(4),SA-8(5),SA-8(6),SA-8(7),SA-8(9),SA-8(11),SA-8(13),SA-8(19),SA-8(29),SA-8(30),SC-32,SC-32(1)}	Security functionality must be intentionally distributed across physical and logical components rather than bolted on post-design. A unified architecture prevents inconsistent enforcement, duplicated controls, or unprotected interfaces. Integrated design reduces attack surface and improves verification of mission-critical protections.
SPR-15	The [spacecraft] shall implement cryptographic mechanisms to identify and reject wireless transmissions that are deliberate attempts to achieve imitative or manipulative communications deception based on signal parameters.{SV-AV-1,SV-IT-1}{AC-3,AC-20,SA-8(19),SC-8(1),SC-23(3),SC-40(3),SI-4(13),SI-4(24),SI-4(25),SI-10(6)}	Adversaries may attempt imitative RF signals to inject commands or manipulate spacecraft behavior. Signal parameter validation (modulation, power, timing, waveform characteristics) strengthens command authentication beyond cryptographic validation alone. This helps mitigate spoofing, replay, and rogue emitter attacks. RF-layer validation complements cryptographic controls.
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-34	The [spacecraft] shall recover to a known cyber-safe state when an anomaly is detected.{IR-4,IR-4(1),SA-8(16),SA-8(19),SA-8(21),SA-8(24),SI-3,SI-4(7),SI-10(6),SI-13,SI-17}
SPR-46	The [spacecraft] shall monitor [Program‑defined telemetry points] for malicious commanding attempts and alert ground operators upon detection.{SV-AC-2,SV-IT-1,SV-DCO-1}{AC-17,AC-17(1),AC-17(10),AU-3(1),RA-10,SC-7,SC-16,SC-16(2),SC-16(3),SI-3(8),SI-4,SI-4(1),SI-4(13),SI-4(24),SI-4(25),SI-10(6)}	Telemetry-based detection enables identification of anomalous command patterns, replay attempts, and injection attacks. Early detection allows rapid containment before mission impact escalates. Onboard monitoring is critical when ground latency limits intervention. This supports proactive defense.
SPR-54	The [spacecraft] shall retain the capability to update/upgrade operating systems while on-orbit.{SV-SP-7}{SA-4(5),SA-8(8),SA-8(31),SA-10(2),SI-3}	The operating system updates should be performed using multi-factor authorization and should only be performed when risk of compromise/exploitation of identified vulnerability outweighs the risk of not performing the update.
SPR-68	The [spacecraft] shall have on-board intrusion detection/prevention system that monitors the mission critical components or systems.{SV-AC-1,SV-AC-2,SV-MA-4}{RA-10,SC-7,SI-3,SI-3(8),SI-4,SI-4(1),SI-4(7),SI-4(13),SI-4(24),SI-4(25),SI-10(6)}	The mission critical components or systems could be GNC/Attitude Control, C&DH, TT&C, Fault Management.
SPR-74	The [organization] shall define the security safeguards that are to be automatically employed when integrity violations are discovered.{SV-IT-2}{CP-2,SA-8(21),SI-3,SI-4(7),SI-4(12),SI-7(5),SI-7(8)}	Predefined safeguards ensure consistent and timely response to detected integrity violations. Ad hoc response increases uncertainty and recovery time. Automated actions may include isolation, reconstitution from gold images, or transition to cyber-safe mode. Defined response paths improve resilience and reduce operator burden during crisis.
SPR-88	The [spacecraft] shall detect and recover from detected memory errors or transitions to a known cyber-safe state.{SV-IT-4,SV-AV-6}{IR-4,IR-4(1),SA-8(16),SA-8(24),SI-3,SI-4(7),SI-10(6),SI-13,SI-17}	Memory corruption may result from radiation, fault injection, or malicious manipulation. Detection prevents silent data corruption from propagating to mission-critical functions. Recovery mechanisms or safe-state transitions preserve availability. Rapid containment supports mission survivability.
SPR-93	The [spacecraft] shall require multi‑factor authorization for: (a) all spacecraft operating system and application updates; (b) updates to task‑scheduling functionality; and (c) creation or update of onboard stored command sequences.{SV-SP-9,SV-SP-11}{AC-3(2),CM-3(8),CM-5,IA-2,PM-12,SA-8(8),SA-8(31),SA-10(2),SI-3(8),SI-7(12),SI-10(6)}	The intent is for multiple checks to be performed prior to executing these SV SW updates. One action is mere act of uploading the SW to the spacecraft. Another action could be check of digital signature (ideal but not explicitly required) or hash or CRC or a checksum. Crypto boxes provide another level of authentication for all commands, including SW updates but ideally there is another factor outside of crypto to protect against FSW updates. Multi-factor authorization could be the "two-man rule" where procedures are in place to prevent a successful attack by a single actor (note: development activities that are subsequently subject to review or verification activities may already require collaborating attackers such that a "two-man rule" is not appropriate).
SPR-97	All [spacecraft] commands which have unrecoverable consequence must have dual authentication prior to command execution. The [spacecraft] shall verify two independent cryptographic approvals prior to execution and shall generate an audit record binding both approver identifiers to the command identifier, time, and outcome.{SV-AC-4,SV-AC-8,SV-AC-2}{AU-9(5),IA-3,IA-4,IA-10,PE-3,PM-12,SA-8(15),SA-8(21),SC-16(2),SC-16(3),SI-3(8),SI-3(9),SI-4(13),SI-4(25),SI-7(12),SI-10(6),SI-13}	Commands with irreversible impact require heightened assurance to prevent catastrophic mission loss. Dual independent cryptographic approvals mitigate insider threat, key compromise, and single-point credential abuse. Binding approver identifiers to the audit trail strengthens accountability and deterrence. This reduces the probability of unauthorized hazardous command execution.
SPR-98	The [spacecraft] shall have a method to ensure the integrity of which have unrecoverable consequence and validate their authenticity before execution.{SV-AC-2,SV-IT-2,SV-IT-1}{AU-9(5),IA-3,IA-4,IA-10,PE-3,PM-12,SA-8(15),SA-8(21),SC-16(2),SC-16(3),SI-3(8),SI-3(9),SI-4(13),SI-4(25),SI-7(12),SI-10(6),SI-13}	Hazardous commands must be cryptographically protected and validated prior to execution. Integrity and authenticity checks prevent replay, modification, or injection of destructive instructions. Without validation, RF interception or command path compromise could result in mission-ending actions. This ensures critical commands are both authorized and unaltered.
SPR-106	The [spacecraft] shall provide non-identical methods, or functionally independent methods, for commanding a mission critical function when the software is the sole control of that function.{AC-3(2),SI-3(8),SI-13}
SPR-128	The [spacecraft] shall accept hazardous commands only when prerequisite checks are satisfied.{SV-AC-8,SV-AV-5}{AC-17(4),SI-10,SI-10(6)}	Precondition validation ensures hazardous commands are executed only under safe system states. This prevents execution under anomalous or compromised conditions. Independent verification reduces false activation risk. Safety and cyber controls must be integrated.
SPR-129	The [spacecraft] shall restrict the use of information inputs to spacecraft and designated ground stations as defined in the applicable ICDs.{SV-AC-1,SV-AC-2}{AC-20,SC-23,SI-10,SI-10(5),SI-10(6)}	Limiting inputs to approved spacecraft and ground stations reduces spoofing and injection risk. ICD-defined boundaries prevent rogue sources from influencing control systems. This constrains trust relationships. Controlled input surfaces reduce attack vectors.
SPR-130	The [spacecraft] shall discriminate between valid and invalid input into the software and rejects invalid input.{SV-SP-1,SV-IT-2}{SC-16(2),SI-3(8),SI-10,SI-10(3),SI-10(6)}	Input validation prevents buffer overflows, injection, and parser exploitation. Rejecting malformed or unexpected data reduces denial-of-service and corruption risks. Deterministic validation improves resilience. Robust input handling is fundamental to secure software.
SPR-131	The [spacecraft] shall identify and reject commands received out-of-sequence when the out-of-sequence commands can cause a hazard/failure or degrade the control of a hazard or mission.{SV-AC-2,SV-AV-4}{SC-16(2),SI-4(13),SI-4(25),SI-10,SI-10(6),SI-13}	Command sequencing enforces operational logic and safety interlocks. Out-of-sequence commands may bypass safeguards. Sequence enforcement prevents replay and control manipulation. This preserves control flow integrity.
SPR-132	The [spacecraft] software subsystems shall accept [Program defined hazardous] commands only when prerequisite checks are satisfied.{SV-MA-3,SV-AV-7}{SI-10}
SPR-133	The [spacecraft] software subsystems shall identify and reject commands received out-of-sequence when the out-of-sequence commands can cause a hazard/failure or degrade the control of a hazard or mission.{SV-MA-3,SV-AV-7}{SI-10}
SPR-134	The [spacecraft] software subsystems shall perform prerequisite checks for the execution of hazardous commands.{SV-MA-3,SV-AV-7}{SI-10}
SPR-135	The [organization] shall ensure that all viable commands are known to the mission and SV "owner.{SV-AC-8}{SI-10,SI-10(3)}	This is a concern for bus re-use. It is possible that the manufacturer left previously coded commands in their syntax rather than starting from a clean slate. This leaves potential backdoors and other functionality the mission does not know about.
SPR-136	The [organization] shall perform analysis of critical (backdoor) commands that could adversely affect mission success if used maliciously.{SV-AC-8}{SI-10,SI-10(3)}	Heritage and commercial products often have many residual operational (e.g., hardware commands) and test capabilities that are unidentified or unknown to the end user, perhaps because they were not expressly stated mission requirements. These would never be tested and their effects unknown, and hence, could be used maliciously. Test commands not needed for flight should be deleted from the flight database.
SPR-137	The [spacecraft] shall only use or include [organization]-defined critical commands for the purpose of providing emergency access where commanding authority is appropriately restricted.{SV-AC-8}{SI-10,SI-10(3)}	The intent is protect against misuse of critical commands. On potential scenario is where you could use accounts with different privileges, could require an additional passphrase or require entry into a different state or append an additional footer to a critical command. There is room for design flexibility here that can still satisfy this requirement.
SPR-138	The [spacecraft] software subsystems shall discriminate between valid and invalid input into the software and rejects invalid input.{SV-MA-3,SV-AV-7}{SI-10,SI-10(3)}
SPR-139	The [spacecraft] software subsystems shall properly handle spurious input and missing data.{SV-MA-3,SV-AV-7}{SI-10,SI-10(3)}
SPR-140	The [spacecraft] shall properly handle spurious input and missing data.{SV-SP-1,SV-AV-6}{SI-10,SI-10(3),SI-10(6)}	Spurious or missing data may indicate attack or fault conditions. Robust handling prevents cascading failures. Defensive programming ensures safe defaults and fallback states. This reduces exploitability of abnormal input conditions.
SPR-141	The [spacecraft] shall perform prerequisite checks for the execution of hazardous commands.{SI-10,SI-10(6),SI-13}
SPR-142	The [spacecraft] shall only use or include critical commands for the purpose of providing emergency access where commanding authority is appropriately restricted.{SI-3(8),SI-10,SI-10(3)}
SPR-143	The [spacecraft] software subsystems shall validate a functionally independent parameter prior to the issuance of any sequence that could remove an inhibit or perform a hazardous action.{SV-MA-3,SV-AV-7}{SI-10(3)}	Independent parameter validation ensures command legitimacy from a secondary data source. This reduces risk of single-variable manipulation. Functional independence increases resilience. Hazardous actions require layered confirmation.
SPR-144	The [spacecraft] shall validate a functionally independent parameter prior to the issuance of any sequence that could remove an inhibit, or perform a hazardous action.{SV-AC-8,SV-MA-3}{SI-10(3),SI-10(6),SI-13}	Redundant validation mechanisms ensure hazardous transitions cannot occur through single-point compromise. Independent parameters strengthen control integrity. This reduces exploit paths for inhibit removal. Critical operations demand dual validation logic.
SPR-229	The [organization] shall protect documentation and Controlled Unclassified Information (CUI) as required, in accordance with the risk management strategy.{SV-CF-3,SV-SP-4,SV-SP-10}{AC-3,CM-12,CP-2,PM-17,RA-5(4),SA-3,SA-3(1),SA-5,SA-10,SC-8(1),SC-28(3),SI-12}	Documentation may reveal architecture details exploitable by adversaries. Proper handling prevents leakage. Protection of CUI supports regulatory compliance. Information governance complements technical controls.
SPR-230	The [organization] shall identify and properly classify mission sensitive design/operations information and access control shall be applied in accordance with classification guides and applicable federal laws, Executive Orders, directives, policies, regulations, and standards.{SV-CF-3,SV-AV-5}{AC-3,CM-12,CP-2,PM-17,RA-5(4),SA-3,SA-3(1),SA-5,SA-8(19),SC-8(1),SC-28(3),SI-12}	* Mission sensitive information should be classified as Controlled Unclassified Information (CUI) or formally known as Sensitive but Unclassified. Ideally these artifacts would be rated SECRET or higher and stored on classified networks. Mission sensitive information can typically include a wide range of candidate material: the functional and performance specifications, the RF ICDs, databases, scripts, simulation and rehearsal results/reports, descriptions of uplink protection including any disabling/bypass features, failure/anomaly resolution, and any other sensitive information related to architecture, software, and flight/ground /mission operations. This could all need protection at the appropriate level (e.g., unclassified, SBU, classified, etc.) to mitigate levels of cyber intrusions that may be conducted against the project’s networks. Stand-alone systems and/or separate database encryption may be needed with controlled access and on-going Configuration Management to ensure changes in command procedures and critical database areas are tracked, controlled, and fully tested to avoid loss of science or the entire mission.
SPR-231	The [organization] shall distribute documentation to only personnel with defined roles and a need to know.{SV-CF-3,SV-AV-5}{CM-12,CP-2,SA-5,SA-10}	Least privilege and need to know should be employed with the protection of all documentation. Documentation can contain sensitive information that can aid in vulnerability discovery, detection, and exploitation. For example, command dictionaries for ground and space systems should be handles with extreme care. Additionally, design documents for missions contain many key elements that if compromised could aid in an attacker successfully exploiting the system.
SPR-232	The [organization] shall conduct a criticality analysis to identify mission critical functions and critical components and reduce the vulnerability of such functions and components through secure system design.{SV-SP-3,SV-SP-4,SV-AV-7,SV-MA-4}{CP-2,CP-2(8),PL-7,PM-11,PM-30(1),RA-3(1),RA-9,SA-8(9),SA-8(11),SA-8(25),SA-12,SA-14,SA-15(3),SC-7(29),SR-1}	During SCRM, criticality analysis will aid in determining supply chain risk. For mission critical functions/components, extra scrutiny must be applied to ensure supply chain is secured.
SPR-233	The [organization] shall identify the applicable physical and environmental protection policies covering the development environment and spacecraft hardware. {SV-SP-4,SV-SP-5,SV-SP-10}{PE-1,PE-14,SA-3,SA-3(1),SA-10(3)}	Development environments must be protected from tampering. Physical controls prevent hardware supply chain compromise. Policy clarity ensures consistent safeguards. Secure development underpins secure deployment.
SPR-234	The [organization] shall develop and document program-specific identification and authentication policies for accessing the development environment and spacecraft. {SV-SP-10,SV-AC-4}{AC-3,AC-14,IA-1,SA-3,SA-3(1)}	Strong authentication prevents unauthorized development access. Development compromise can introduce malicious code. Documented policies ensure consistent enforcement. Identity governance supports supply chain integrity.
SPR-235	The [organization] shall ensure security requirements/configurations are placed in accordance with NIST 800-171 with enhancements in 800-172 on the development environments to prevent the compromise of source code from supply chain or information leakage perspective.{SV-SP-4,SV-SP-10,SV-CF-3}{AC-3,SA-3,SA-3(1),SA-15}	Supply chain threats target development environments. Enhanced controls reduce risk of source code exfiltration. Compliance strengthens contractual and regulatory assurance. Development security directly impacts spacecraft integrity.
SPR-236	The [organization] shall implement a verifiable flaw remediation process into the developmental and operational configuration management process.{SV-SP-1,SV-SP-6,SV-SP-7,SV-SP-9,SV-SP-11}{CA-2,CA-5,SA-3,SA-3(1),SA-11,SI-3,SI-3(10)}	The verifiable process should also include a cross reference to mission objectives and impact statements. Understanding the flaws discovered and how they correlate to mission objectives will aid in prioritization.
SPR-237	The [organization] shall establish robust procedures and technical methods to perform testing to include adversarial testing (i.e.abuse cases) of the platform hardware and software.{SV-SP-2,SV-SP-1}{CA-8,CP-4(5),RA-5,RA-5(1),RA-5(2),SA-3,SA-4(3),SA-11,SA-11(1),SA-11(2),SA-11(5),SA-11(7),SA-11(8),SA-15(7)}	Abuse-case testing reveals design weaknesses before deployment. Red-teaming strengthens defensive posture. Proactive validation reduces operational risk. Testing must simulate realistic threat scenarios.
SPR-238	The [organization] shall require subcontractors developing information system components or providing information system services (as appropriate) to demonstrate the use of a system development life cycle that includes [state-of-the-practice system/security engineering methods, software development methods, testing/evaluation/validation techniques, and quality control processes].{SV-SP-1,SV-SP-2,SV-SP-3,SV-SP-9}{SA-3,SA-4(3)}	Select the particular subcontractors, software vendors, and manufacturers based on the criticality analysis performed for the Program Protection Plan and the criticality of the components that they supply. Examples of good security practices would be using defense-in-depth tactics across the board, least-privilege being implemented, two factor authentication everywhere possible, using DevSecOps, implementing and validating adherence to secure coding standards, performing static code analysis, component/origin analysis for open source, fuzzing/dynamic analysis with abuse cases, etc.
SPR-245	The [organization] shall define processes and procedures to be followed when integrity verification tools detect unauthorized changes to software, firmware, and information.{SV-IT-2}{CM-3,CM-3(1),CM-3(5),CM-5(6),CM-6,CP-2,IR-6,IR-6(2),PM-30,SC-16(1),SC-51,SI-3,SI-4(7),SI-4(24),SI-7,SI-7(7),SI-7(10)}	Predefined response procedures reduce reaction time. Clear escalation paths improve containment. Consistent handling prevents confusion during incidents. Preparedness strengthens resilience.
SPR-259	The [organization] shall develop an incident response and forensics plan that covers the spacecrafts.{SV-MA-5}{CP-2,IR-1,IR-3,IR-3(2),IR-4(12),IR-4(13),IR-8,SA-15(10),SI-4(24)}	A structured response plan enables coordinated containment and recovery. Forensics planning ensures evidence preservation. Defined procedures reduce confusion during crisis. Incident readiness enhances resilience.
SPR-280	The [organization] shall require the developer of the system, system component, or system service to deliver the system, component, or service with [Program-defined security configurations] implemented.{SV-SP-1,SV-SP-9}{SA-4(5)}	For the spacecraft FSW, the defined security configuration could include to ensure the software does not contain a pre-defined list of Common Weakness Enumerations (CWEs)and/or CAT I/II Application STIGs.
SPR-292	The [organization] shall ensure that role-based security-related training is provided to personnel with assigned security roles and responsibilities: (i) before authorizing access to the system or performing assigned duties; (ii) when required by system changes; and (iii) at least annually thereafter.{SV-AC-4}{AT-3,CP-2}	Personnel must understand role-specific responsibilities. Tailored training reduces misuse. Continuous reinforcement maintains awareness. Human factors are central to defense.
SPR-293	The [organization] shall employ techniques to limit harm from potential adversaries identifying and targeting the [organization]s supply chain.{SV-SP-4,SV-SP-5,SV-SP-6}{CP-2,PM-30,SA-9,SA-12(5),SC-38,SR-3,SR-3(1),SR-3(2),SR-5(2)}	Adversaries often exploit supplier relationships. Protective measures reduce reconnaissance and manipulation. Supply chain resilience strengthens mission integrity. Proactive defense mitigates systemic exposure.
SPR-389	The [organization] shall perform analysis of critical backdoor commands that could adversely affect mission success if used maliciously.{SV-AC-8}{SI-10,SI-10(3)}	Backdoor or maintenance commands may bypass safeguards if misused. Analysis identifies high-impact commands requiring additional controls. Understanding abuse potential reduces catastrophic misuse. Preventive governance strengthens operational assurance.
SPR-435	For FPGA pre-silicon artifacts that are developed, coded, and tested by a developer that is not accredited, the [organization] shall be subjected to a development environment and pre-silicon artifacts risk assessment by [organization]. Based on the results of the risk assessment, the [organization] may need to implement protective measures or other processes to ensure the integrity of the FPGA pre-silicon artifacts.{SV-SP-5}{SA-3,SA-3(1),SA-8(9),SA-8(11),SA-12,SA-12(1),SR-1,SR-5}	DOD-I-5200.44 requires the following: 4.c.2 “Control the quality, configuration, and security of software, firmware, hardware, and systems throughout their lifecycles... Employ protections that manage risk in the supply chain… (e.g., integrated circuits, field-programmable gate arrays (FPGA), printed circuit boards) when they are identifiable (to the supplier) as having a DOD end-use. “ 4.e “In applicable systems, integrated circuit-related products and services shall be procured from a Trusted supplier accredited by the Defense Microelectronics Activity (DMEA) when they are custom-designed, custommanufactured, or tailored for a specific DOD military end use (generally referred to as application-specific integrated circuits (ASIC)). “ 1.g “In coordination with the DOD CIO, the Director, Defense Intelligence Agency (DIA), and the Heads of the DOD Components, develop a strategy for managing risk in the supply chain for integrated circuit-related products and services (e.g., FPGAs, printed circuit boards) that are identifiable to the supplier as specifically created or modified for DOD (e.g., military temperature range, radiation hardened).
SPR-436	The [organization] shall require the developer of the system, system component, or system services to demonstrate the use of a system development life cycle that includes [state-of-the-practice system/security engineering methods, software development methods, testing/evaluation/validation techniques, and quality control processes].{SV-SP-1,SV-SP-2,SV-SP-3,SV-SP-9}{SA-3,SA-4(3)}	Examples of good security practices would be using defense-in-depth tactics across the board, least-privilege being implemented, two factor authentication everywhere possible, using DevSecOps, implementing and validating adherence to secure coding standards, performing static code analysis, component/origin analysis for open source, fuzzing/dynamic analysis with abuse cases, etc.
SPR-516	The [organization] shall define,and the [spacecraft] shall enforce,guardrails for any unauthenticated discovery beacons (if used), limiting content to non‑sensitive signals that cannot enable timing/key inference, preventing state change via those paths, narrowing content in safe mode, and validating behavior in simulators/flatsats.{SV-CF-2,SV-IT-1}{AC-4,AC-14}	Discovery mechanisms can leak sensitive timing or state information. Guardrails restrict beacon content to non-sensitive data. Controlled discovery reduces inference risk.
SPR-530	The [spacecraft] shall enable selected maintenance capabilities only within time‑bounded and mode‑bounded windows, audit enable/disable events, auto‑revert on timeout/reset, and expose enabled/disabled capability state in telemetry.{SV-AC-8,SV-AC-4}{CM-7,CM-7(2),SA-8,SA-8(14),AC-3}	Maintenance capabilities expand risk surface. Time-limited activation reduces abuse window. Telemetry exposure ensures oversight. Auto-revert strengthens containment.
SPR-538	The [spacecraft] shall budget CPU/power/memory for security functions (crypto, logging, verification), implement graceful degradation (e.g., summarize logs, throttle verification) that preserves TT&C and safing, and expose telemetry showing throttling decisions and residual capacity.{SV-AV-1,SV-DCO-1}{PE-9,SA-8(8),SC-6,CP-2}	Security must not starve essential TT&C. Explicit resource budgeting ensures sustained enforcement. Graceful degradation preserves mission priority. Telemetry visibility supports oversight.
SPR-540	The [spacecraft] shall employ deterministic scheduling where feasible and bound retries/timeouts on command/telemetry paths by mode, exposing retry counters, backoff state, and finite‑state transitions in telemetry with consistent error/reject reason codes.{SV-IT-4,SV-AV-1}{SA-8(12),SI-10(3),SI-13}	Determinism prevents runaway retries or timing exploitation. Exposed counters support diagnosis. Finite-state transitions strengthen transparency. Predictable behavior improves assurance.