Process White Listing

Simple process ID whitelisting on the firmware level could impede attackers from instigating unnecessary processes which could impact the spacecraft

NIST Rev5 Controls

D3FEND Techniques

D3FEND Artifacts

ISO 27001

NASA Best Practice Guide

MI-DCO-01

ESA Space Shield Mitigation

None

Related MITRE EMB3D Mitigations

Related CSF 2.0

Related BSI Security Measures

No related BSI Security Measures

ID: CM0069

Tier: I

Ground CM

Created: 2022/10/19

Last Modified: 2023/10/17

Techniques Addressed by Countermeasure

ID		Name	Description
EX-0010		Malicious Code	The adversary achieves on-board effects by introducing executable logic that runs on the vehicle, either native binaries and scripts, injected shellcode, or “data payloads” that an interpreter treats as code (e.g., procedure languages, table-driven automations). Delivery commonly piggybacks on legitimate pathways: software/firmware updates, file transfer services, table loaders, maintenance consoles, or command sequences that write to executable regions. Once staged, activation can be explicit (a specific command, mode change, or file open), environmental (time/geometry triggers), or accidental, where operator actions or routine autonomy invoke the implanted logic. Malicious code can target any layer it can reach: altering flight software behavior, manipulating payload controllers, patching boot or device firmware, or installing hooks in drivers and gateways that bridge bus and payload traffic. Effects range from subtle logic changes (quiet data tampering, command filtering) to overt actions (forced mode transitions, resource starvation), and may include secondary capabilities like covert communications, key material harvesting, or persistence across resets by rewriting images or configuration entries.
	.01	Ransomware	Ransomware on a spacecraft encrypts data or critical configuration so that nominal operations can no longer proceed without the attacker’s cooperation. Targets include mass-memory file stores (engineering telemetry, payload data), configuration and command tables, event logs, on-board ephemerides, and even intermediate buffers used by downlink pipelines. Some variants interfere with key services instead of bulk data, e.g., encrypting a command dictionary or table index so valid inputs are rejected, or wrapping the payload data path in an attacker-chosen cipher so downlinked products appear as noise. By denying access to on-board content or control artifacts at scale, attackers convert execution into bargaining power or irreversible mission degradation.
	.02	Wiper Malware	Wipers deliberately destroy or irreversibly corrupt data and, in some cases, executable images to impair or end mission operations. Destructive routines may overwrite with patterns or pseudorandom data, repeatedly reformat volumes, trigger wear mechanisms on non-volatile memory, or manipulate low-level translation layers so recovery tools see a blank or inconsistent device. Activation can be immediate or staged, sleeping until a specific time, pass, or maintenance action, and may be paired with anti-recovery steps such as erasing checksums, undo logs, or golden images. Because wipers operate at storage and image layers that underpin many subsystems, collateral effects can cascade: autonomy enters safing without viable recovery paths, downlinks carry only noise, and subsequent updates cannot be authenticated or applied. The defining feature is irreversible loss of data or executables as the primary objective, rather than concealment or monetization.
	.03	Rootkit	A rootkit hides the presence and activity of other malicious components by interposing on the mechanisms that report system state. On spacecraft this can occur within flight software processes, at OS kernel level, inside separation kernels/hypervisors, or down in system firmware where drivers and initialization routines run. Techniques include API and syscall hooking, patching message queues and inter-process communication paths, altering task lists and scheduler views, filtering telemetry packets and event logs, and rewriting sensor or health values before they are recorded or downlinked. Rootkits may also hook command handlers and gateways so certain opcodes, timetags, or sources are silently accepted or ignored while external observers see normal acknowledgments. Because many missions rely on deterministic procedures and limited observability, even small alterations to reporting can make malicious actions appear as plausible mode transitions or benign anomalies. Persistence often pairs with the concealment layer, with the rootkit reinjecting companions after resets or rebuilds by monitoring for specific files, tables, or image loads and modifying them on the fly.
	.04	Bootkit	A bootkit positions itself in the pre-OS boot chain so that it executes before normal integrity checks and can shape what the system subsequently trusts. After seizing early control, the bootkit can redirect image selection, patch kernels or flight binaries in memory, adjust device trees and driver tables, or install hooks that persist across warm resets. Some variants maintain shadow copies of legitimate images and present them to basic verification routines while steering actual execution to a modified payload; others manipulate fallback logic so recovery modes load attacker-controlled code. Because the boot path initializes memory maps, buses, and authentication material, a bootkit can also influence key/counter setup and gateway configurations, creating conditions favorable to later tactics. The central characteristic is precedence: by running first, the implant defines the reality higher layers observe, ensuring that every subsequent component launches under conditions curated by the attacker.
EX-0012		Modify On-Board Values	The attacker alters live or persistent data that the spacecraft uses to make decisions and route work. Targets include device and control registers, parameter and limit tables, internal routing/subscriber maps, schedules and timelines, priority/QoS settings, watchdog and timer values, autonomy/FDIR rule tables, ephemeris and attitude references, and power/thermal setpoints. Many missions expose legitimate mechanisms for updating these artifacts, direct memory read/write commands, table load services, file transfers, or maintenance procedures, which can be invoked to steer behavior without changing code. Edits may be transient (until reset) or latched/persistent across boots; they can be narrowly scoped (a single bit flip on an enable mask) or systemic (rewriting a routing table so commands are misdelivered). The effect space spans subtle biasing of control loops, selective blackholing of commands or telemetry, rescheduling of operations, and wholesale changes to mode logic, all accomplished by modifying the values the software already trusts and consumes.
	.01	Registers	Threat actors may target the internal registers of the victim spacecraft in order to modify specific values as the FSW is functioning or prevent certain subsystems from working. Most aspects of the spacecraft rely on internal registers to store important data and temporary values. By modifying these registers at certain points in time, threat actors can disrupt the workflow of the subsystems or onboard payload, causing them to malfunction or behave in an undesired manner.
	.02	Internal Routing Tables	Threat actors may rewrite the maps that tell software where to send and receive things. In publish/subscribe or message-queued flight frameworks, tables map message IDs to subscribers, opcodes to handlers, and pipes to processes; at interfaces, address/port maps define how traffic traverses bridges and gateways (e.g., SpaceWire node/port routes, 1553 RT/subaddress mappings, CAN IDs). By altering these structures, commands can be misdelivered, dropped, duplicated, or routed through unintended paths; telemetry can be redirected or blackholed; and handler bindings can be swapped so an opcode triggers the wrong function. Schedule/routing hybrids, used to sequence activities and distribute results, can be edited to reorder execution or to create feedback loops that occupy bandwidth and processor time. The result is control over who hears what and when, achieved by changing the lookup tables that underpin command/telemetry distribution rather than the code that processes them.
	.03	Memory Write/Loads	The adversary uses legitimate direct-memory commands or load services to place chosen bytes at chosen addresses. Many spacecraft support raw read/write operations, block loads into RAM or non-volatile stores, and table/file loaders that copy content into working memory. With knowledge of address maps and data structures, an attacker can patch function pointers or vtables, alter limit and configuration records, seed scripts or procedures into interpreter buffers, adjust DMA descriptors, or overwrite portions of executable images resident in RAM. Loads may be sized and paced to fit link and queue constraints, then activated by a subsequent command, mode change, or natural reference by the software.
	.04	App/Subscriber Tables	In publish/subscribe flight frameworks, applications and subsystems register interest in specific message classes via subscriber (or application) tables. These tables map message IDs/topics to subscribers, define delivery pipes/queues, and often include filters, priorities, and rate limits. By altering these mappings, an adversary can quietly reshape information flow: critical consumers stop receiving health or sensor messages; non-critical tasks get flooded; handlers are rebound so an opcode or message ID reaches the wrong task; or duplicates create feedback loops that consume bandwidth and CPU. Because subscription state is usually read at init or refreshed on command, subtle edits can persist across reboots or take effect at predictable times. Similar effects appear in legacy MIL-STD-1553 deployments by modifying Remote Terminal (RT), subaddress, or mode-code configurations so that messages are misaddressed or dropped at the bus interface. The net result is control-by-misdirection: the software still “works,” but the right data no longer reaches the right recipient at the right time.
	.05	Scheduling Algorithm	Spacecraft typically rely on real-time scheduling, fixed-priority or deadline/periodic schemes, driven by timers, tick sources, and per-task parameters. Threat actors target these parameters and associated tables to skew execution order and timing. Edits may change priorities, periods, or deadlines; adjust CPU budgets and watchdog thresholds; alter ready-queue disciplines; or reconfigure timer tick rates and clock sources. They may also modify task affinities, message-queue depths, and interrupt masks so preemption and latency characteristics shift. Small changes can have large effects: high-rate control loops see added jitter, estimator updates miss deadlines, command/telemetry handling starves, or low-priority maintenance tasks monopolize cores due to mis-set periods. Manipulated schedules can create intermittent, state-dependent malfunctions that are hard to distinguish from environmental load. The essence of the technique is to weaponize time, reshaping when work happens so that otherwise correct code produces unsafe or exploitable behavior.
	.06	Science/Payload Data	Payload data, and the metadata that gives it meaning, can be altered in place to steal value, mislead users, or degrade mission outputs. Targets include raw detector frames, packetized Level-0 streams, onboard preprocessed products, and file catalogs/directories on mass memory. Adjacent metadata such as timestamps, pointing/attitude tags, calibration coefficients, compression settings, and quality flags are equally potent; slight bias in a calibration table or time tag can skew entire downlink campaigns while appearing routine. An adversary may rewrite frame headers, reorder packets, substitute segments from prior passes, or flip quality bits so ground pipelines silently discard or misclassify products. Recorder index manipulation can orphan files or cause downlinks to serve stale or fabricated content. Because many missions perform some processing or filtering onboard, tampering upstream of downlink propagates forward as “authoritative” truth, jeopardizing mission objectives without obvious protocol anomalies.
	.07	Propulsion Subsystem	Propulsion relies on parameters and sensed values that govern burns, pressure management, and safing. Editable items include thruster calibration and minimum impulse bit, valve timing and duty limits, inhibit masks, delta-V tables, plume keep-out constraints, tank pressure/temperature thresholds, leak-detection limits, and momentum-management coupling with attitude control. By modifying these, an adversary can provoke over-correction, waste propellant through repeated trims, bias orbit maintenance, or trigger protective sequences at inopportune times. False pressure or temperature readings can cause autonomous venting or lockouts; tweaked alignment matrices or misapplied gimbal limits can yield off-axis thrust and attitude excursions; altered desaturation rules can induce frequent wheel unloads that sap resources. Because consumables are finite and margins tight, even modest parameter drift can shorten mission life or violate keep-out and conjunction constraints while presenting as “normal” control activity.
	.08	Attitude Determination & Control Subsystem	ADCS depends on tightly coupled models and parameters: star-tracker catalogs and masks, sensor alignments and bias terms, gyro scale factors and drift rates, estimator covariances and process/measurement noise, controller gains and saturation limits, wheel/CMG torque constants, magnetic torquer maps, and sun sensor thresholds. Editing these values skews estimation or control, producing slow bias, limit cycles, loss of lock, or abrupt safing triggers. For example, a small change to a star-tracker mask can force frequent dropouts; an inflated gyro bias drives the filter away from truth; softened actuator limits or mis-set gains let disturbances accumulate; altered sun-point entry criteria cause unnecessary mode switches. Secondary impacts propagate to power, thermal, and communications because pointing and geometry underpin array generation, radiator view factors, and antenna gain. The technique turns the spacecraft against itself by nudging the parameters that close the loop between what the vehicle believes and how it responds.
	.09	Electrical Power Subsystem	Adversaries alter parameters and sensed values that govern power generation, storage, and distribution so the spacecraft draws or allocates energy in harmful ways. Editable items include bus voltage/current limits, MPPT setpoints and sweep behavior, array and SADA modes, battery charge/discharge thresholds and temperature derates, state-of-charge estimation constants, latching current limiter (LCL) trip/retry settings, load-shed priorities, heater duty limits, and survival/keep-alive rules. By changing these, a threat actor can drive excess consumption (e.g., disabling load shed, raising heater floors), misreport remaining energy (skewed SoC), or push batteries outside healthy ranges, producing brownouts, repeated safing, or premature capacity loss. Manipulating thresholds and hysteresis can also create oscillations where loads repeatedly drop and re-engage, wasting energy and stressing components. The effect is accelerated depletion or misallocation of finite power, degrading mission operations and potentially preventing recovery after eclipse or anomalies.
	.10	Command & Data Handling Subsystem	C&DH relies on tables and runtime values that define how commands are parsed, queued, and dispatched and how telemetry is collected, stored, and forwarded. Targets include opcode-to-handler maps, argument limits and schemas, queue depths and priorities, message ID routing, publish/subscribe bindings, timeline/schedule entries, file catalog indices, compression and packetization settings, and event/telemetry filters. Edits to these artifacts reshape control and visibility: commands are delayed, dropped, or misrouted; telemetry is suppressed or redirected; timelines slip; and housekeeping/data products are repackaged in ways that confuse ground processing. Because many frameworks treat these values as authoritative configuration, small changes can silently propagate across subsystems, degrading responsiveness, creating backlogs, or severing the logical pathways that keep the vehicle coordinated, without modifying the underlying code.
	.11	Watchdog Timer (WDT)	Watchdogs supervise liveness by requiring software to “pet” within defined windows or the system resets. Threat actors manipulate WDT behavior by changing timeout durations, windowed-WDT bounds, reset actions, enable/mask bits, or the source that performs the petting (e.g., moving it into a low-level ISR so higher layers can be stalled indefinitely). Software WDTs can be disabled or starved; hardware WDTs are influenced via control registers, strap pins, or supervisor commands that alter prescalers and reset ladders. Outcomes include preventing intended resets so runaway tasks consume power and bandwidth, or forcing repeated resets at tactically chosen moments, e.g., during updates or handovers, to keep the system in a degraded or easily predictable state. The technique converts a safety mechanism into a tool for either unbounded execution or rhythmic disruption, depending on how the WDT parameters are rewritten.
	.12	System Clock	Spacecraft maintain multiple time bases and distribute time to schedule sequences, validate timetags, manage anti-replay counters, and align navigation/attitude processing. By writing to clock registers, altering time-distribution services, switching disciplining sources, or biasing oscillator parameters, an adversary can skew these references. Effects include reordering or prematurely firing stored command sequences, invalidating timetag checks, desynchronizing counters used by authentication or ranging, misaligning estimator windows, and corrupting timestamped payload data. Even small offsets can accumulate into observable misbehavior when autonomy and scheduling depend on tight temporal guarantees. The result is execution that happens at the wrong moment, or not at all, because the system’s notion of “now” has been shifted.
	.13	Poison AI/ML Training Data	When missions employ AI/ML, for onboard detection/classification, compression, anomaly screening, guidance aids, or ground-side planning, training data becomes a control surface. Data poisoning inserts crafted examples or labels into the training corpus or fine-tuning set so the resulting model behaves incorrectly while appearing valid. Variants include clean-label backdoors (benign-looking samples with a hidden trigger that later induces a targeted response), label flipping and biased sampling (to skew decision boundaries), and corruption of calibration/ground-truth products that the pipeline trusts. For space systems, poisoning may occur in science archives, test vectors, simulated scenes, or housekeeping datasets used to train autonomy/anomaly models; models trained on poisoned corpora are then packaged and uplinked as routine updates. Once fielded, a simple trigger pattern in imagery, telemetry, or RF features can cause misclassification, suppression, or false positives at the time and place the adversary chooses, turning model behavior into an execution mechanism keyed by data rather than code.
DE-0003		On-Board Values Obfuscation	The adversary manipulates housekeeping and control values that operators and autonomy rely on to judge activity, health, and command hygiene. Targets include command/telemetry counters, event/severity flags, downlink/reporting modes, cryptographic-mode indicators, and the system clock. By rewriting, freezing, or biasing these fields, and by selecting reduced or summary telemetry modes, unauthorized actions can proceed while the downlinked picture appears routine or incomplete. The result is delayed recognition, misattribution to environmental effects, or logs that cannot be reconciled post-facto.
	.01	Vehicle Command Counter (VCC)	The VCC tracks how many commands the spacecraft has accepted. An adversary masks activity by zeroing, freezing, or selectively decrementing the VCC, or by steering actions through paths that do not increment it (maintenance dictionaries, alternate receivers, hidden handlers). They may also overwrite the telemetry field that reports the VCC so ground displays show a lower or steady count while high volumes of commands are processed. This breaks simple “command volume” heuristics and makes bursty activity look normal.
	.02	Rejected Command Counter	This counter records commands that failed checks or were refused. To hide probing and trial-and-error, the adversary suppresses increments, periodically clears the value, or forges the downlinked field so rejection rates appear benign. Variants also tamper with associated reason codes or event entries, replacing them with innocuous outcomes. Analysts reviewing telemetry see no evidence of failed attempts even as the system is being exercised aggressively.
	.03	Command Receiver On/Off Mode	By toggling receiver enable states (per-receiver, per-antenna, or per-band), the adversary creates deliberate “quiet windows” in which outside intervention cannot arrive. Turning a command receiver off, or shifting to a configuration that ignores the primary path, allows queued actions or onboard procedures to run without interruption, while operators perceive a transient loss of commandability consistent with geometry or environment. Brief, well-timed toggles can also desynchronize counters and handovers, complicating reconstruction of what occurred.
	.04	Command Receivers Received Signal Strength	Threat actors may target the on-board command receivers received signal parameters (i.e., automatic gain control (AGC)) in order to stop specific commands or signals from being processed by the spacecraft. For ground controllers to communicate with spacecraft in orbit, the on-board receivers need to be configured to receive signals with a specific signal to noise ratio (ratio of signal power to the noise power). Targeting values related to the antenna signaling that are modifiable can prevent the spacecraft from receiving ground commands.
	.05	Command Receiver Lock Modes	Receivers advertise acquisition states, bit lock, frame lock, and command lock, that indicate readiness to accept telecommands. Adversaries leverage these indicators in two ways: (1) use command-lock tests to validate geometry, power, Doppler, and polarization without risking visible command execution; and (2) tamper with the values that report lock status so ground views never show that lock was achieved. Techniques include freezing or clearing lock flags and counters, raising/lowering internal thresholds so lock occurs without being reported (or vice versa), and timing brief lock intervals between telemetry samples. The result is a window where the spacecraft is receptive to commands while downlinked status suggests otherwise.
	.06	Telemetry Downlink Modes	Spacecraft expose modes that control what telemetry is sent and how, real-time channels, recorder playback, beacon/summary only, event-driven reporting, and per-virtual-channel/APID selections. By switching modes or editing the associated parameters (rates, filters, playback queues, index ranges), an adversary can thin, defer, or reroute observability. Typical effects include suppressing high-rate engineering streams in favor of minimal beacons, delaying playback of time periods of interest, replaying benign segments, or redirecting packets to alternate virtual channels that are not routinely monitored. Telemetry continues to flow, but it no longer reflects the activity the operators need to see.
	.07	Cryptographic Modes	Many missions separate authentication from confidentiality and allow on-orbit selection of algorithms, keys, profiles, or “crypto off/clear” states. Adversaries manipulate these mode controls and selectors to desynchronize ground and space or to hide content: flipping to a profile that the ground is not using, requesting clear telemetry while maintaining authenticated uplink, or rotating key IDs so frames validate internally but appear undecodable to external tools. Mode indicators and status words can also be biased so ground displays show expected settings while the link actually operates under attacker-chosen parameters, masking command and data exchanges within normal-looking traffic.
	.08	Received Commands	Spacecraft typically maintain histories of accepted, rejected, and executed commands, buffers, logs, or file records that can be downlinked on demand or periodically. An adversary conceals activity by editing or pruning these artifacts: removing entries, altering opcodes or arguments, rewriting timestamps and source identifiers, rolling logs early, or repopulating with benign-looking commands to balance counters. Related acknowledgments and event records may be suppressed or reclassified so cross-checks appear consistent. After manipulation, the official command history shows a plausible narrative that omits or mischaracterizes the adversary’s actions.
	.09	System Clock for Evasion	The adversary biases the spacecraft’s authoritative time so that telemetry, event logs, and command histories appear shifted or inconsistent. By writing clock registers, altering disciplining sources (e.g., GNSS vs. free-running oscillator), or tweaking distribution services and offsets, they can make stored commands execute “earlier” or “later” on the timeline and misalign acknowledgments with actual actions. Downlinked frames still carry plausible timestamps near packet headers, but those stamps no longer reflect when data was produced, complicating reconstruction of sequences and masking causality during incident analysis.
	.10	GPS Ephemeris	A satellite with a GPS receiver can use ephemeris data from GPS satellites to estimate its own position in space. A hostile actor could spoof the GPS signals to cause erroneous calculations of the satellite’s position. The received ephemeris data is often telemetered and can be monitored for indications of GPS spoofing. Reception of ephemeris data that changes suddenly without a reasonable explanation (such as a known GPS satellite handoff), could provide an indication of GPS spoofing and warrant further analysis. Threat actors could also change the course of the vehicle and falsify the telemetered data to temporarily convince ground operators the vehicle is still on a proper course.
	.11	Watchdog Timer (WDT) for Evasion	By modifying watchdog parameters or who “pets” them, an adversary shapes what evidence survives. Extending or disabling timeouts allows long-running processes to operate without forced resets that would expose abnormal CPU or power usage; conversely, shortening windows or relocating the petting source to a low-level ISR can induce frequent resets that wipe volatile traces, break correlation in logs, and explain anomalies as “spurious reboots.” In both directions, the watchdog becomes a timing tool for hiding activity rather than a guardrail against it.
	.12	Poison AI/ML Training for Evasion	When security monitoring relies on AI/ML (e.g., anomaly detection on telemetry, RF fingerprints, or command semantics), the training data itself is a target. Data-poisoning introduces crafted examples or labels so the learned model embeds false associations, treating attacker behaviors as normal, or flagging benign patterns instead. Variants include clean-label backdoors keyed to subtle triggers, label flipping that shifts decision boundaries, and biased sampling that suppresses rare-but-critical signatures. Models trained on tainted corpora are later deployed as routine updates; once in service, the adversary presents inputs containing the trigger or profile they primed, and the detector omits or downranks the very behaviors that would reveal the intrusion.
DE-0007		Evasion via Rootkit	A rootkit hides malicious activity by interposing on reporting paths after the system has booted. In flight contexts this includes patching flight software APIs, kernel syscalls, message queues, and telemetry publishers so task lists, counters, health channels, and event severities are falsified before downlink. Command handlers can be hooked to suppress evidence of certain opcodes or sources; recorder catalogs and file listings can be rewritten on the fly; and housekeeping can be biased to show nominal temperatures, currents, or voltages while actions proceed. The defining feature is runtime concealment: the observability surfaces operators rely on are altered to present a curated, benign narrative.
DE-0008		Evasion via Bootkit	A bootkit hides activity by running first and shaping what higher layers will later observe. Positioned in boot ROM handoff or early loaders, it can select or patch images in memory, alter device trees and driver tables, seed forged counters and timestamps, and preconfigure telemetry/crypto modes so subsequent components launch into a reality curated by the attacker. Because integrity and logging mechanisms are initialized afterward, the resulting view of processes, files, and histories reflects the bootkit’s choices, allowing long-term evasion that persists across resets and mode transitions.

Space Threats Addressed by Countermeasure

ID	Description
SV-MA-3	Attacks on critical software subsystems Attitude Determination and Control (AD&C) subsystem determines and controls the orientation of the satellite. Any cyberattack that could disrupt some portion of the control loop - sensor data, computation of control commands, and receipt of the commands would impact operations Telemetry, Tracking and Commanding (TT&C) subsystem provides interface between satellite and ground system. Computations occur within the RF portion of the TT&C subsystem, presenting cyberattack vector Command and Data Handling (C&DH) subsystem is the brains of the satellite. It interfaces with other subsystems, the payload, and the ground. It receives, validate, decodes, and sends commands to other subsystems, and it receives, processes, formats, and routes data for both the ground and onboard computer. C&DH has the most cyber content and is likely the biggest target for cyberattack. Electrical Power Subsystem (EPS) provides, stores, distributes, and controls power on the satellite. An attack on EPS could disrupt, damage, or destroy the satellite.
SV-SP-3	Introduction of malicious software such as a virus, worm, Distributed Denial-Of-Service (DDOS) agent, keylogger, rootkit, or Trojan Horse
SV-SP-6	Software reuse, COTS dependence, and standardization of onboard systems using building block approach with addition of open-source technology leads to supply chain threat
SV-DCO-1	Not knowing that you were attacked, or attack was attempted

Sample Requirements

SPARTA ID	Requirement	Rationale/Additional Guidance/Notes
SPR-7	The [organization] shall document and design a security architecture using a defense-in-depth approach that allocates the [organization]s defined safeguards to the indicated locations and layers: [Examples include: operating system abstractions and hardware mechanisms to the separate processors in the platform, internal components, and the FSW].{SV-MA-6}{CA-9,PL-7,PL-8,PL-8(1),SA-8(3),SA-8(4),SA-8(7),SA-8(9),SA-8(11),SA-8(13),SA-8(19),SA-8(29),SA-8(30)}	Spacecraft security cannot rely on a single control; layered defenses reduce the likelihood of catastrophic compromise. Documenting safeguard allocation across hardware, OS, firmware, and FSW ensures coverage across attack surfaces. This supports resiliency against both cyber intrusion and supply chain weaknesses. Clear documentation enables verification and independent assessment.
SPR-8	The [organization] shall ensure that the allocated security safeguards operate in a coordinated and mutually reinforcing manner.{SV-MA-6}{CA-7(5),PL-7,PL-8(1),SA-8(19)}	Independent controls that operate in isolation may create security gaps or conflicting behaviors. Coordinated safeguards ensure that encryption, authentication, partitioning, and monitoring functions reinforce each other rather than undermine availability or safety. This reduces bypass risk and improves fault/cyber response integration. Cohesive operation is essential for resilient mission assurance.
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-145	The [spacecraft] mission/cyber critical commands shall be "complex" or diverse from other commands so that a single bit flip could not transform a benign command into a hazardous command.{SV-MA-3,SV-AV-7}{SI-10(5)}	Complex command encoding reduces risk of single-bit errors causing hazardous action. Diversity prevents accidental transformation into destructive instructions. This protects against radiation-induced bit flips and malicious bit manipulation. Safety and cyber resiliency intersect here.
SPR-146	The [spacecraft] shall provide at least one independent command for each operator-initiated action used to shutdown a function leading to or reducing the control of a hazard.{SV-MA-5,SV-MA-3}{SI-10(5)}	Independent shutdown commands ensure operators retain control during anomalous conditions. Redundant control paths reduce systemic failure risk. This supports safe recovery from hazardous states. Separation enhances mission survivability.
SPR-147	The [spacecraft] software subsystems shall provide at least one independent command for each operator-initiated action used to shut down a function leading to or reducing the control of a hazard.{SV-MA-3,SV-AV-7}{SI-10(5)}
SPR-153	The [spacecraft] operating system, if COTS or FOSS, shall be selected from a [organization]-defined acceptance list.{SV-SP-7}{CM-7(8),CM-7(5)}	Selecting OS from approved list reduces exposure to unvetted vulnerabilities. Controlled selection supports maintainability and patch governance. This mitigates risk from insecure or unsupported platforms. Trusted baselines simplify compliance verification.
SPR-155	The [organization] shall ensure that software planned for reuse meets the fit, form, and function, and security as a component within the new application.{SV-SP-6,SV-SP-7,SV-SP-11}{CM-7(5)}	Reused components may introduce hidden vulnerabilities. Validation ensures compatibility and security alignment with new mission context. Prior approval does not guarantee safe reuse. Rigorous assessment prevents latent risk inheritance.
SPR-405	The [organization] shall define/maintain an approved operating system list for use on spacecraft.{SV-SP-7}{CM-7(5)}	The operating system is extremely important to security and availability of the spacecraft, therefore should receive high levels of assurance that it operates as intended and free of critical weaknesses/vulnerabilities.
SPR-479	The [organization] shall define, baseline, and maintain the purposing of the space platform and link segment, including intended objectives, authorized capabilities, prohibited functions, and operational constraints, and shall use this baseline to bound requirements, updates, and on-orbit operations.{SV-AC-8,SV-MA-6}{PM-32,PL-8}	Defining authorized and prohibited functions prevents scope creep. Clear purposing bounds updates and operational use. Governance limits misuse potential. Structured baseline supports disciplined operations.
SPR-531	The [spacecraft] shall enforce whitelisting for executable images and mission scripts/procedures by ID, hash, or signature, accept only artifacts produced by the mission build pipeline, and constrain interpreters/macros to sandboxed contexts with provenance checks on inputs.{SV-SP-9,SV-SP-4}{CM-7,CM-7(5),CM-7(8),SI-7}	Accepting only pipeline-produced artifacts prevents unauthorized code execution. Hash/signature validation ensures integrity. Sandbox constraints limit interpreter abuse. Provenance enforcement strengthens defense.