ID	Name	Description
IA-0003	Crosslink via Compromised Neighbor	Where spacecraft exchange data over inter-satellite links (RF or optical), a compromise on one vehicle can become a bridgehead to others. Threat actors exploit crosslink trust: shared routing, time distribution, service discovery, or gateway functions that forward commands and data between vehicles and ground. With knowledge of crosslink framing, addressing, and authentication semantics, an adversary can craft traffic that appears to originate from a trusted neighbor, injecting control messages, malformed service advertisements, or payload tasking that propagates across the mesh. In tightly coupled constellations, crosslinks may terminate on gateways that also touch the C&DH or payload buses, providing additional pivot opportunities. Because crosslink traffic is expected and often high volume, attacker activity can be timed to blend with synchronization intervals, ranging exchanges, or scheduled data relays.
IA-0004	Secondary/Backup Communication Channel	Adversaries pursue alternative paths to the spacecraft that differ from the primary TT&C in configuration, monitoring, or authentication. Examples include backup MOC/ground networks, contingency TT&C chains, maintenance or recovery consoles, low-rate emergency beacons, and secondary receivers or antennas on the vehicle. These channels exist to preserve commandability during outages, safing, or maintenance; they may use different vendors, legacy settings, or simplified procedures. Initial access typically pairs reconnaissance of failover rules with actions that steer operations onto the backup path, natural events, induced denial on the primary, or simple patience until scheduled tests and handovers occur. Once traffic flows over the alternate path, the attacker leverages its distinct procedures, dictionaries, or rate/size limits to introduce commands or data that would be harder to inject on the primary.
IA-0004.02	Receiver	Threat actors may target the spacecraft’s secondary (backup) RF receive path, often a differently sourced radio, alternate antenna/feed, or cross-strapped front end that is powered or enabled under specific modes. Threat actors map when the backup comes into play (safing, antenna obscuration, maintenance, link degradation) and what command dictionaries, framing, or authentication it expects. If the backup receiver has distinct waveforms, counters, or vendor defaults, the attacker can inject traffic that is accepted only when that path is active, limiting exposure during nominal ops. Forcing conditions that enable the backup, jamming the primary, exploiting geometry, or waiting for routine tests, creates the window for first execution. The result is a foothold gained through a rarely used RF path, exploiting differences in implementation and operational cadence between primary and standby receive chains.
IA-0008	Rogue External Entity	Adversaries obtain a foothold by interacting with the spacecraft from platforms outside the authorized ground architecture. A “rogue external entity” is any actor-controlled transmitter or node, ground, maritime, airborne, or space-based, that can radiate or exchange traffic using mission-compatible waveforms, framing, or crosslink protocols. The technique exploits the fact that many vehicles must remain commandable and discoverable over wide areas and across multiple modalities. Using public ephemerides, pass predictions, and knowledge of acquisition procedures, the actor times transmissions to line-of-sight windows, handovers, or maintenance periods. Initial access stems from presenting traffic that the spacecraft will parse or prioritize: syntactically valid telecommands, crafted ranging/acquisition exchanges, crosslink service advertisements, or payload/user-channel messages that bridge into the command/data path.
IA-0008.01	Rogue Ground Station	Adversaries may field their own ground system, transportable or fixed, to transmit and receive mission-compatible signals. A typical setup couples steerable apertures and GPS-disciplined timing with SDR/modems configured for the target’s bands, modulation/coding, framing, and beacon structure. Using pass schedules and Doppler/polarization predictions, the actor crafts over-the-air traffic that appears valid at the RF and protocol layers.
IA-0008.02	Rogue Spacecraft	Adversaries may employ their own satellite or hosted payload to achieve proximity and a privileged RF geometry. After phasing into the appropriate plane or drift orbit, the rogue vehicle operates as a local peer: emitting narrow-beam or crosslink-compatible signals, relaying user-channel traffic that the target will honor, or advertising services that appear to originate from a trusted neighbor. Close range reduces path loss and allows highly selective interactions, e.g., targeted spoofing of acquisition exchanges, presentation of crafted routing/time distribution messages, or injection of payload tasking that rides established inter-satellite protocols. The rogue platform can also perform spectrum and protocol reconnaissance in situ, refining message formats and timing before attempting first execution.
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.
LM-0003	Constellation Hopping via Crosslink	In networks where vehicles exchange data over inter-satellite links, a compromise on one spacecraft becomes a springboard to others. The attacker crafts crosslink traffic, routing updates, service advertisements, time/ephemeris distribution, file or tasking messages, that appears to originate from a trusted neighbor and targets gateway functions that bridge crosslink traffic into command/data paths. Once accepted, those messages can queue procedures, deliver configuration/table edits, or open file transfer sessions on adjacent vehicles. In mesh or hub-and-spoke constellations, this enables “hop-by-hop” spread: a single foothold uses shared trust and protocol uniformity to reach additional satellites without contacting the ground segment.