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MI-DCO-02 - Mission Fault Management

Principle

The mission should incorporate fault management bypass protection in its requirements and resulting system.

Rationale

The mission should consider the possibility of fault management transitions to bypass the system's protection measures and incorporate these considerations. Fault management systems may be deliberately triggered in an effort to bypass the system's protective measures. For example, safehold mode operations without command-link protection.

Related Countermeasures

ID Name Description NIST Rev 5
CM0001 Protect Sensitive Information Space mission sensitive information spans a broad attack surface and must be inventoried, classified, and protected at a level commensurate with its sensitivity across every location where it resides, including ground systems, contractor networks, and remote access environments. Sensitive material typically includes functional and performance specifications, interface control documents (ICDs), command and telemetry (C&T) databases, uplink protection schemes including disable and bypass features, fault management logic, scripts, simulation and rehearsal results, failure and anomaly resolution records, and architecture and software documentation. Each information type must be assigned a protection level, such as unclassified, controlled, proprietary, or classified, and access must be restricted to personnel with defined roles and a verified need to know. Sensitive data shall be protected at rest and in transit using encryption or other mission-approved safeguards commensurate with its classification, sensitivity, threat exposure, and operational constraints. DLP capabilities shall be applied to systems and data flows where they are technically feasible and effective, with alternative access controls, monitoring, or information-flow protections used where conventional DLP technology is not suitable. Ongoing configuration management must track, control, and document all changes to command procedures and critical database content to prevent unauthorized modification and mission degradation. AC-25 AC-3(11) AC-4(23) AC-4(25) AC-4(6) CA-3 CM-12 CM-12(1) PL-8 PL-8(1) PM-11 PM-17 SA-3 SA-3(1) SA-3(2) SA-4(12) SA-5 SA-8 SA-8(19) SA-9(7) SC-16 SC-16(1) SC-8(1) SC-8(3) SI-12 SI-21 SI-23 SR-12 SR-7
CM0020 Threat modeling Threat modeling is a structured analytical process that identifies, enumerates, and prioritizes potential threats to a system by systematically examining assets, trust boundaries, data flows, and adversary capabilities relative to the system's architecture. Applied in combination with attack surface analysis and vulnerability analysis, threat modeling produces an integrated picture of where the system is most exposed and what the consequences of successful exploitation would be. Analysis should draw on findings from similar systems, components, or services where applicable, leveraging documented threat experience from comparable missions or architectures to avoid re-learning known lessons. The outputs of threat modeling must directly inform design decisions throughout the development process, with attack surface reduction treated as a design objective rather than a post-development hardening activity: interfaces, services, protocols, and code paths that are not necessary to mission function should be eliminated or constrained before they become embedded in the architecture. Threat model artifacts should be treated as living documents, updated as the system design evolves and as new threat intelligence becomes available. CA-3 CM-4 CP-2 PL-8 PL-8(1) RA-3 SA-11 SA-11(2) SA-11(3) SA-11(6) SA-15(6) SA-15(8) SA-2 SA-3 SA-4(9) SA-8 SA-8(25) SA-8(30)
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
CM0002 COMSEC Communications security (COMSEC) denies unauthorized parties access to information derived from telecommunications while ensuring the authenticity of those communications. COMSEC is commonly defined as a broad discipline that may encompass cryptographic security, transmission security, emissions security, cryptographic key management, traffic-flow security, and physical security of COMSEC material. Within SPARTA, these areas are further broken down through separate countermeasures, including CM0029 | TRANSEC, CM0030 | Crypto Key Management, CM0003 | TEMPEST/EMSEC, and CM0073 | Traffic Flow Analysis Defense. CM0002 provides the overarching communications-security context and supports the coordinated application of these specialized countermeasures. All mission links, particularly telemetry, tracking, and commanding (TT&C) links, should employ communications-security protections appropriate to the sensitivity, criticality, operational environment, and threat exposure of the information being exchanged. These protections may include cryptographic protection, transmission security, emissions security, traffic-flow protection, secure key management, and physical protection of COMSEC material, as addressed by the applicable specialized countermeasures. Spacecraft should not provide an operational mode that permits required cryptographic protection or command authentication on TT&C links to be bypassed or disabled. Operational, maintenance, test, recovery, and contingency modes should be considered when evaluating whether communications-security protections can be unintentionally or improperly circumvented. Communication receivers and associated signal-processing or TRANSEC mechanisms should detect and, when mission-defined criteria are met, reject or otherwise safely handle transmissions exhibiting anomalous signal characteristics consistent with communications deception. Cryptographic mechanisms should authenticate and integrity-check received content but should not be treated as RF-deception detectors. AC-17 AC-17(1) AC-17(10) AC-17(2) AC-18 AC-18(1) AC-2(11) AC-3(10) CA-3 IA-4(9) IA-5 IA-5(7) IA-7 PL-8 PL-8(1) SA-8(18) SA-8(19) SA-9(6) SC-10 SC-12 SC-12(1) SC-12(2) SC-12(3) SC-12(6) SC-13 SC-16(3) SC-28(1) SC-28(3) SC-7 SC-7(10) SC-7(11) SC-7(18) SC-7(5) SC-8(1) SC-8(3) SI-10 SI-10(3) SI-10(5) SI-10(6) SI-19(4) SI-3(8)
CM0034 Monitor Critical Telemetry Points Monitoring defined spacecraft telemetry points provides a key source of evidence for detecting adversary activity against on-orbit systems, where observability is largely limited to the events and conditions the spacecraft can sense, record, and report. Monitored telemetry must include both accepted and rejected commands, command mode transitions, command counters, and other indicators of commanding activity, enabling detection of unauthorized command attempts that fail authentication as well as anomalous patterns in legitimate command traffic. Monitoring scope should include RF and link-quality indicators that support detection and triage of interference or suspected jamming. These indicators should be correlated with expected link conditions and other available evidence before hostile activity is concluded. Security-relevant telemetry should be integrated and time-correlated with ground-based defensive cyber operations infrastructure, including security information and event management (SIEM) and audit platforms, to provide unified space-system cybersecurity situational awareness. The resulting view should correlate spacecraft observations with relevant ground-system security events while accounting for telemetry latency, contact availability, and other observability limitations. AC-17(1) AU-3(1) CA-7(6) IR-4(14) PL-8 PL-8(1) SA-8(13) SC-16 SC-16(1) SC-7 SI-3(8) SI-4(7)
CM0070 Alternate Communications Paths Establishing alternate communications paths for spacecraft and ground system operations reduces the likelihood that a single adversarial event, physical disruption, or technical failure will deny all mission communications. Reliance on a single communications pathway creates a single point of failure that adversaries can exploit through jamming, denial of service against ground infrastructure, physical disruption of a ground station, or compromise of network connectivity, any of which could result in complete loss of commanding and telemetry capability. Alternate paths must be assessed end to end for shared failure modes and operational dependencies. Differences in frequency, ground station, relay service, or network provider provide meaningful resilience only when the paths do not remain dependent on the same critical spacecraft, ground, management, or service infrastructure. The selection and configuration of alternate paths must be governed by the mission's concept of operations (CONOPS), which defines the conditions under which each path is used, the priority and switchover procedures between paths, and the minimum communications capability that must be maintained to satisfy mission safety and operational continuity requirements. AC-17 CP-2 CP-4(2) CP-8(3) PL-8 PL-8(1) SC-47
CM0006 Cloaking Safe-mode Safe-mode entry represents a high-risk transition point at which a spacecraft enters a reduced-capability state to preserve vehicle safety and support anomaly recovery. This transition must not create a less secure command, telemetry, or onboard processing environment. To the extent permitted by mission safety and recovery requirements, the spacecraft should avoid unnecessary or uniquely identifying changes in transmission characteristics, beacon content, communication cadence, and externally observable behavior that would allow an adversary to reliably identify and exploit the safe-mode state. Safe-mode shall preserve the mission-defined minimum security posture for every communication path and command mechanism that remains active. This posture should include authentication, data integrity, anti-replay protection, command authorization, command validation, cryptographic key protection, security-relevant logging, and encryption where confidentiality is required. The spacecraft shall not enter a crypto-bypass or unauthenticated command state solely because safe-mode has been activated. The safe-mode software and configuration baseline shall explicitly define the security controls, command dictionaries, alternate receivers, contingency communication paths, rate and size limits, command counters, time tag requirements, interlocks, logging functions, and monitoring capabilities that remain active during safe-mode. These protections shall be designed and verified as part of the safe-mode baseline rather than treated as discretionary functions that may be removed without security impact analysis. CP-12 CP-2 PL-8 PL-8(1) SC-13 SC-16 SC-24 SC-8
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)
CM0042 Robust Fault Management The fault management system is a high-privilege, autonomous spacecraft function that adversaries may attempt to exploit as an attack vector, triggering protective responses that place the spacecraft in a degraded or more vulnerable operational state. Attack scenarios include manipulating sensor, state, or telemetry information to induce onboard or ground-directed safing actions; creating false fault conditions through sensor spoofing or proximity operations; exploiting safe-mode configurations that reduce security protections; and inducing autonomous maneuver responses through crafted fault indications. Robust fault management requires that safing procedures and autonomous responses be designed with explicit security analysis confirming that each protective action does not introduce a more exploitable system state than the fault condition it responds to. The integrity and authenticity of sensor data, state information, commands, and telemetry used by onboard or ground-based fault management functions must be protected to prevent falsified inputs from triggering unintended responses. Every fault response, including mode transitions, actuator commands, and communication reconfigurations, must be evaluated against the question of whether an adversary could deliberately induce that response and whether the resulting system state provides the adversary with meaningful advantage. CP-2 CP-4(5) IR-3 IR-3(1) IR-3(2) PE-10 PE-11 PE-11(1) PE-14 PL-8 PL-8(1) SA-3 SA-4(5) SA-8 SA-8(13) SA-8(24) SA-8(26) SA-8(3) SA-8(30) SA-8(4) SC-16(2) SC-24 SC-5 SI-13 SI-13(4) SI-17 SI-4(13) SI-4(7) SI-7(5)
CM0044 Cyber-safe Mode Cyber-safe mode is a dedicated, configuration-controlled spacecraft operating state entered autonomously or by authorized ground command when mission-defined conditions indicate a credible threat to platform integrity. In this state, nonessential functions are shut down or isolated and the spacecraft operates from an integrity-protected, validated software and configuration baseline. Unlike traditional safe mode, which addresses hardware faults and operational anomalies, cyber-safe mode is specifically designed to respond to cyber threats, providing a secure recovery baseline from which the spacecraft can reconstitute compromised functions. Authentication and encryption must remain enabled within cyber-safe mode, ensuring that the reduced operational state does not degrade the security posture of the vehicle. The cyber-safe mode software and configuration must be stored onboard using hardware-based protections that prevent modification by nominal flight software, ordinary commands, and other untrusted execution paths. Where baseline updates are permitted, they must use a separately authorized and integrity-verified maintenance process that preserves a recoverable trusted version. Following entry into cyber-safe mode, the spacecraft must be capable of reconstituting firmware and software functions to pre-attack capability levels, either autonomously through self-healing mechanisms or with ground assistance, and must be capable of replanning operations based on whatever equipment remains available after the cyber event. The primary recovery objective is restoration of full mission capability; where that is not achievable, the spacecraft should attain the maximum reduced mission capability available given the post-attack system state. CP-10 CP-10(4) CP-12 CP-2 CP-2(5) IR-3 IR-3(1) IR-3(2) IR-4 IR-4(12) IR-4(3) PE-10 PE10 PL-8 PL-8(1) SA-3 SA-8 SA-8(10) SA-8(12) SA-8(13) SA-8(19) SA-8(21) SA-8(23) SA-8(24) SA-8(26) SA-8(3) SA-8(4) SC-16(2) SC-24 SC-5 SI-11 SI-17 SI-4(7) SI-7(17) SI-7(5)
CM0068 Reinforcement Learning A reinforcement learning (RL) agent deployed within the spacecraft or ground system can provide an adaptive, autonomous anomaly detection and response capability that identifies anomalous events, including malicious data inputs and injected commands, and redirects affected processes to proceed safely by ignoring or isolating the malicious input. An RL agent learns a response policy that maps observations to actions according to its training environment and reward function. It may generalize to scenarios not explicitly included in training, but its ability to detect or respond correctly to novel attacks or conditions outside the validated operational envelope must not be assumed. Anomaly detection may be incorporated into the RL architecture or provided by a separate monitoring function. Effective deployment requires separate protections against compromise of the training process and manipulation of observations presented to the deployed agent. Online learning or policy adaptation should be disabled unless specifically authorized, bounded, and validated. Agent-selected responses must be constrained by a trusted safety mechanism. IR-5 IR-5(1) SI-4 SI-4(2)
CM0043 Backdoor Commands All commands capable of being executed on the spacecraft must be known, documented, and accounted for by the mission and spacecraft owner; the existence of undisclosed or undocumented commands, whether introduced by developers, component suppliers, or subsystem vendors, represents an unacceptable and unmanageable risk to mission integrity. Commands capable of adversely affecting mission success if misused must be identified through deliberate analysis and protected by mission-defined authorization and execution controls commensurate with their consequences. Commands that bypass normal operational safeguards require additional justification and restrictions appropriate to their emergency or contingency purpose. Backdoor, residual, hardware-level, test, diagnostic, or override commands that bypass normal operational pathways or safeguards should be retained only where mission-approved emergency or contingency access requires them. Their inclusion must be explicitly justified, and their commanding authority must be appropriately restricted. Hazardous commands required for normal mission operations are not prohibited by this countermeasure but must be governed by approved authorization, prerequisite, sequencing, and safety controls. Any command capability introduced by a subsystem supplier or component vendor that was not explicitly requested or authorized by the mission owner must be identified, evaluated, and either removed or brought under formal mission command governance before launch. AC-14 CP-2 SA-3 SA-4(5) SA-8 SI-10 SI-10(3) SI-10(6) SI-3(8)
CM0045 Error Detection and Correcting Memory Error detection and correcting (EDAC) memory provides a foundational defense against radiation-induced corruption in spacecraft onboard memory. The selected EDAC scheme must detect and correct error patterns within its designed capability and identify errors that exceed that capability. Common single-error-correction, double-error-detection schemes correct single-bit errors and detect double-bit errors, but other schemes may provide different correction and detection capabilities. The EDAC scheme must be integrated with both the fault management system and the spacecraft's cyber-protection mechanisms, enabling coordinated responses to uncorrectable multi-bit errors that go beyond time-delayed ground monitoring of EDAC telemetry. This integration is security-relevant because multi-bit memory errors, whether radiation-induced or adversarially induced through deliberate fault injection, can corrupt flight software, configuration data, or security-critical parameters in ways that create exploitable system states if not detected and responded to promptly and autonomously. The spacecraft must use the selected EDAC architecture to detect and correct errors during memory access and, where applicable, perform periodic memory scrubbing to detect and remove latent correctable errors. The implementation must identify the affected memory address or region for detected uncorrectable errors involving two or more bits, to the extent supported by the memory architecture, with higher-order detection or correction provided where required by mission risk. Detection of an uncorrectable error must trigger a timely onboard fault-management or cyber-protection response that prevents continued use or propagation of suspect data and autonomously minimizes adverse effects without waiting for ground detection. Subsequent diagnosis and recovery may be autonomous, ground-directed, or combined according to mission requirements. CP-2 SA-3 SA-8 SI-16
CM0029 TRANSEC Transmission security (TRANSEC) is the component of communications security (COMSEC) concerned with protecting the characteristics of the transmission itself, as distinct from protecting the content of the information being communicated. TRANSEC controls reduce the likelihood, effectiveness, or operational impact of transmission interception, signal disruption, communications deception, and exploitation of transmission characteristics within the defined threat model. Applicable TRANSEC techniques include jam-resistant waveforms that increase resistance to jamming and communications deception, spread spectrum and frequency hopping techniques that reduce signal predictability and improve resistance to interception and disruption, low probability of intercept and low probability of detection (LPI/LPD) signal designs that reduce transmission observability, and transmission scheduling or pattern discipline that limits the intelligence value of traffic analysis. TRANSEC requirements should be applied to mission communication links according to link criticality (e.g., TT&C, crosslinks), threat exposure, and operational consequence. TRANSEC must be treated as a distinct layer of protection complementary to, but not a substitute for, cryptographic protection of information content. AC-17 AC-18 AC-18(5) CA-3 CP-8 PL-8 PL-8(1) SA-8(19) SC-16 SC-16(1) SC-40 SC-40(1) SC-40(3) SC-40(4) SC-5 SC-8(1) SC-8(3) SC-8(4)