Monitor Critical Telemetry Points

Monitor defined telemetry points for malicious activities (i.e., jamming attempts, commanding attempts (e.g., command modes, counters, etc.)). This would include valid/processed commands as well as commands that were rejected. Telemetry monitoring should synchronize with ground-based Defensive Cyber Operations (i.e., SIEM/auditing) to create a full space system situation awareness from a cybersecurity perspective.

Best Segment for Countermeasure Deployment

  • Ground Segment

NIST Rev5 Controls

D3FEND

ISO 27001

ID: CM0034
D3FEND Artifacts: 
Created: 2022/10/19
Last Modified: 2022/10/19

Techniques Addressed by Countermeasure

here here here here here here here here here
ID Name Description
IA-0003 Crosslink via Compromised Neighbor Threat actors may compromise a victim SV via the crosslink communications of a neighboring SV that has been compromised. SVs in close proximity are able to send commands back and forth. Threat actors may be able to leverage this access to compromise other SVs once they have access to another that is nearby.
IA-0007 Compromise Ground Station Threat actors may initially compromise the ground station in order to access the target SV. Once compromised, the threat actor can perform a multitude of initial access techniques, including replay, compromising FSW deployment, compromising encryption keys, and compromising authentication schemes.
.01 Compromise On-Orbit Update Threat actors may manipulate and modify on-orbit updates before they are sent to the target SV. This attack can be done in a number of ways, including manipulation of source code, manipulating environment variables, on-board table/memory values, or replacing compiled versions with a malicious one.
.02 Malicious Commanding via Valid GS Threat actors may compromise target owned ground systems components (e.g., front end processors, command and control software, etc.) that can be used for future campaigns or to perpetuate other techniques. These ground systems components have already been configured for communications to the victim SV. By compromising this infrastructure, threat actors can stage, launch, and execute an operation. Threat actors may utilize these systems for various tasks, including Execution and Exfiltration.
IA-0008 Rogue External Entity Threat actors may gain access to a victim SV through the use of a rogue external entity. With this technique, the threat actor does not need access to a legitimate ground station or communication site.
.01 Rogue Ground Station Threat actors may gain access to a victim SV through the use of a rogue ground system. With this technique, the threat actor does not need access to a legitimate ground station or communication site.
.02 Rogue Spacecraft Threat actors may gain access to a target SV using their own SV that has the capability to maneuver within close proximity to a target SV to carry out a variety of TTPs (i.e., eavesdropping, side-channel, etc.). Since many of the commercial and military assets in space are tracked, and that information is publicly available, attackers can identify the location of space assets to infer the best positioning for intersecting orbits. Proximity operations support avoidance of the larger attenuation that would otherwise affect the signal when propagating long distances, or environmental circumstances that may present interference.
IA-0009 Trusted Relationship Access through trusted third-party relationship exploits an existing connection that has been approved for interconnection. Leveraging third party / approved interconnections to pivot into the target systems is a common technique for threat actors as these interconnections typically lack stringent access control due to the trusted status.
.02 Vendor Threat actors may target the trust between vendors and the target space vehicle. Missions often grant elevated access to vendors in order to allow them to manage internal systems as well as cloud-based environments. The vendor's access may be intended to be limited to the infrastructure being maintained but it may provide laterally movement into the target space vehicle. Attackers may leverage security weaknesses in the vendor environment to gain access to more critical mission resources or network locations. In the space vehicle context vendors may have direct commanding and updating capabilities outside of the primary communication channel.
EX-0001 Replay Replay attacks involve threat actors recording previously data streams and then resending them at a later time. This attack can be used to fingerprint systems, gain elevated privileges, or even cause a denial of service.
.01 Command Packets Threat actors may interact with the victim SV by replaying captured commands to the SV. While not necessarily malicious in nature, replayed commands can be used to overload the target SV and cause it's onboard systems to crash, perform a DoS attack, or monitor various responses by the SV. If critical commands are captured and replayed, thruster fires, then the impact could impact the SV's attitude control/orbit.
EX-0013 Flooding Threat actors use jamming and flooding attacks to disrupt communications by injecting unexpected noise or messages into a transmission channel. There are several types of attacks that are consistent with this method of exploitation, and they can produce various outcomes. Although, the most prominent of the impacts are denial of service or data corruption. Several elements of the space vehicle may be targeted by jamming and flooding attacks, and depending on the time of the attack, it can have devastating results to the availability of the system.
.02 Erroneous Data Threat actors inject noise into the target channel so that legitimate messages cannot be correctly processed due to data integrity impacts. Additionally, while this technique does not utilize valid commands, the target SV still must consume computing resources to process and discard the signal.
.01 Valid Commands Threat actors may utilize valid commanding as a mechanism for flooding as the processing of these valid commands could expend valuable resources like processing power and battery usage. Flooding the spacecraft bus, sub-systems or link layer with valid commands can create temporary denial of service conditions for the space vehicle while the SV is consumed with processing these valid commands.
EXF-0001 Replay Threat actors may exfiltrate data by replaying commands and capturing the telemetry or payload data as it is sent down. One scenario would be the threat actor replays commands to downlink payload data once SV is within certain location so the data can be intercepted on the downlink by threat actor ground terminals.
PER-0003 Ground System Presence Threat actors may compromise target owned ground systems that can be used for persistent access to the SV or to perpetuate other techniques. These ground systems have already been configured for communications to the victim SV. By compromising this infrastructure, threat actors can stage, launch, and execute persistently.
DE-0002 Prevent Downlink Threat actors may target the downlink connections to prevent the victim SV from sending telemetry to the ground controllers. Telemetry is the only method in which ground controllers can monitor the health and stability of the SV while in orbit. By disabling this downlink, threat actors may be able to stop mitigations from taking place.
.02 Jam Link Signal Threat actors may overwhelm/jam the downlink signal to prevent transmitted telemetry signals from reaching their destination without severe modification/interference, effectively leaving ground controllers unaware of vehicle activity during this time. Telemetry is the only method in which ground controllers can monitor the health and stability of the SV while in orbit. By disabling this downlink, threat actors may be able to stop mitigations from taking place.
DE-0004 Masquerading Threat actors may gain access to a victim SV by masquerading as an authorized entity. This can be done several ways, including through the manipulation of command headers, spoofing locations, or even leveraging Insider's access (i.e., Insider Threat)
LM-0003 Constellation Hopping via Crosslink Threat actors may attempt to command another neighboring spacecraft via crosslink. SVs in close proximity are often able to send commands back and forth. Threat actors may be able to leverage this access to compromise another SV.

Space Threats Addressed by Countermeasure

ID Description

Low-Level Requirements

Requirement Rationale/Additional Guidance/Notes
The [organization] shall implement automated mechanisms to assist in the execution and implementation of the Continuous Monitoring Program (CMP).{CA-7(6)}
The [spacecraft] shall monitor security relevant telemetry points for malicious commanding attempts.{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)}
The [spacecraft] shall generate cyber-relevant audit records containing information that establishes what type of event occurred, when the event occurred, where the event occurred, the source of the event, and the outcome of the event.{SV-DCO-1}{AU-3,AU-3(1),AU-12,IR-4,IR-4(1),RA-10,SI-3,SI-3(10),SI-4(7),SI-4(24)}
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.
The [spacecraft] shall monitor [Program defined telemetry points] for malicious commanding attempts.{SV-AC-1,SV-AC-2}{SC-7,AU-3(1),AC-17(1)} Source from AEROSPACE REPORT NO. TOR-2019-02178 Vehicle Command Counter (VCC) - Counts received valid commands Rejected Command Counter - Counts received invalid commands Command Receiver On/Off Mode - Indicates times command receiver is accepting commands Command Receivers Received Signal Strength - Analog measure of the amount of received RF energy at the receive frequency Command Receiver Lock Modes - Indicates when command receiver has achieved lock on command signal Telemetry Downlink Modes - Indicates when the satellite’s telemetry was transmitting Cryptographic Modes - Indicates the operating modes of the various encrypted links Received Commands - Log of all commands received and executed by the satellite System Clock - Master onboard clock GPS Ephemeris - Indicates satellite location derived from GPS Signals