Detection of unauthorized modifications to the downlink frequency configuration settings, suggesting a potential attack to disrupt the spacecraft's ability to transmit telemetry.

STIX Pattern

[x-opencti-radio-configuration:downlink_frequency != 'authorized_value' AND x-opencti-radio-configuration:modification_time != 'scheduled_window']

SPARTA TTPs

ID	Name	Description
EX-0003	Modify Authentication Process	The adversary alters how the spacecraft validates authority so that future inputs are accepted on their terms. Modifications can target code (patching flight binaries, hot-patching functions in memory, hooking command handlers), data (changing key identifiers, policy tables, or counter initialization), or control flow (short-circuiting MAC checks, widening anti-replay windows, bypassing interlocks on specific opcodes). Common choke points include telecommand verification routines, bootloader or update verifiers, gateway processors that bridge payload and bus traffic, and maintenance dictionaries invoked in special modes. Subtle variants preserve outward behavior, producing normal-looking acknowledgments and counters, while internally accepting a broader set of origins, opcodes, or timetags. Others introduce conditional logic so the backdoor only activates under specific geometry or timing, masking during routine audit. Once resident, the modified process becomes the new trust oracle, enabling recurring execution for the attacker and, in some cases, denying legitimate control by causing authentic inputs to fail verification or to be deprioritized.
DE-0002	Disrupt or Deceive Downlink	Threat actors may target ground-side telemetry reception, processing, or display to disrupt the operator’s visibility into spacecraft health and activity. This may involve denial-based attacks that prevent the spacecraft from transmitting telemetry to the ground (e.g., disabling telemetry links or crashing telemetry software), or more subtle deception-based attacks that manipulate telemetry content to conceal unauthorized actions. Since telemetry is the primary method ground controllers rely on to monitor spacecraft status, any disruption or manipulation can delay or prevent detection of malicious activity, suppress automated or manual mitigations, or degrade trust in telemetry-based decision support systems.
DE-0002.01	Inhibit Ground System Functionality	Threat actors may utilize access to the ground system to inhibit its ability to accurately process, render, or interpret spacecraft telemetry, effectively leaving ground controllers unaware of the spacecraft’s true state or activity. This may involve traditional denial-based techniques, such as disabling telemetry software, corrupting processing pipelines, or crashing display interfaces. In addition, more subtle deception-based techniques may be used to falsify telemetry data within the ground system , such as modifying command counters, acknowledgments, housekeeping data, or sensor outputs , to provide the appearance of nominal operation. These actions can suppress alerts, mask unauthorized activity, or prevent both automated and manual mitigations from being initiated based on misleading ground-side information. Because telemetry is the primary method by which ground controllers monitor the health, behavior, and safety of the spacecraft, any disruption or falsification of this data directly undermines situational awareness and operational control.
DE-0002.03	Inhibit Spacecraft Functionality	In this variant, telemetry is suppressed at the source by manipulating on-board generation or transmission. Methods include disabling or pausing telemetry publishers, altering packet filters and rates, muting event/report channels, reconfiguring recorder playback, retuning/muting transmitters, or switching to modes that emit only minimal beacons. The spacecraft continues operating, but the downlink no longer reflects true activity or arrives too sparsely to support monitoring. By constraining what is produced or transmitted, the adversary reduces opportunities for detection while other actions proceed.
DE-0003.06	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.
EXF-0006	Modify Communications Configuration	The adversary alters radio/optical link configuration so the spacecraft emits mission data over paths the program does not monitor or control. Levers include retuning carriers, adding sidebands or subcarriers, changing modulation/coding profiles, remapping virtual channels/APIDs, editing beacon content, or redirecting routing tables in regenerative payloads. Data can be embedded steganographically (idle fields, padding, frame counters, pilot tones) or carried on a covert auxiliary downlink/crosslink pointed at attacker-owned apertures. Because these emissions conform to plausible waveforms and scheduler behavior, they appear as ordinary link activity while quietly conveying payload products, housekeeping, or file fragments to non-mission receivers.
EXF-0006.01	Software Defined Radio	Programmable SDRs let an attacker introduce new waveforms or piggyback payloads into existing ones. By modifying DSP chains (filters, mixers, FEC, framing), the actor can: add a low-rate subcarrier under the main modulation, alter preamble/pilot sequences to encode bits, vary puncturing/interleaver patterns as a covert channel, or schedule brief “maintenance” bursts that actually carry exfiltrated data. Changes may be packaged as legitimate updates or configuration profiles so the SDR transmits toward attacker-visible geometry using standard equipment, while mission tooling interprets the emission as routine.
EXF-0006.02	Transponder	On bent-pipe or regenerative transponders, configuration controls what is translated, amplified, and routed. An adversary can remap input–output paths, shift translation frequencies, adjust polarization or gain to favor non-mission receivers, or enable auxiliary ports so selected virtual channels or recorder playbacks are forwarded outside the planned ground segment. In regenerative systems, edited routing tables or QoS rules can mirror traffic to an attacker-controlled endpoint. The result is a sanctioned-looking carrier that quietly delivers mission data to unauthorized listeners.