SV-AV-4 - Scheduling Table Attack

Attacking the scheduling table to affect tasking

Informational References

  • CENTRA Volume I - Cyber Content of Satellites
DiD Layer: S/C Software
CAPEC #:  186 | 533
NIST Rev5 Control Tag Mapping:  AC-3 | AC-3(2) | CA-7 | CA-7(6) | CP-4 | CP-4(5) | RA-10 | SA-8 | SA-8(21) | SA-8(24) | SA-11 | SA-11(9) | SC-45 | SC-45(1) | SC-45(2)
Lowest Threat Tier to
Create Threat Event:  
Notional Risk Rank Score: 19

High-Level Requirements

The spacecraft shall ensure any update to task scheduling functionality has met high assurance standards before execution.

Low-Level Requirements

Requirement Rationale/Additional Guidance/Notes
The spacecraft shall require multi-factor authorization for all updates to the task scheduling functionality within the spacecraft. {SV-AV-4} {AC-3(2)}

Related SPARTA Techniques and Sub-Techniques

ID Name Description
EX-0012 Modify On-Board Values Threat actors may perform specific commands in order to modify onboard values that the victim spacecraft relies on. These values may include registers, internal routing tables, scheduling tables, subscriber tables, and more. Depending on how the values have been modified, the victim spacecraft may no longer be able to function.
EX-0012.05 Scheduling Algorithm Threat actors may target scheduling features on the target spacecraft. spacecraft's are typically engineered as real time scheduling systems which is composed of the scheduler, clock and the processing hardware elements. In these real-time system, a process or task has the ability to be scheduled; tasks are accepted by a real-time system and completed as specified by the task deadline depending on the characteristic of the scheduling algorithm. Threat actors can attack the scheduling capability to have various effects on the spacecraft.
IMP-0001 Deception (or Misdirection) Measures designed to mislead an adversary by manipulation, distortion, or falsification of evidence or information into a system to induce the adversary to react in a manner prejudicial to their interests. Threat actors may seek to deceive mission stakeholders (or even military decision makers) for a multitude of reasons. Telemetry values could be modified, attacks could be designed to intentionally mimic another threat actor's TTPs, and even allied ground infrastructure could be compromised and used as the source of communications to the spacecraft.
IMP-0002 Disruption Measures designed to temporarily impair the use or access to a system for a period of time. Threat actors may seek to disrupt communications from the victim spacecraft to the ground controllers or other interested parties. By disrupting communications during critical times, there is the potential impact of data being lost or critical actions not being performed. This could cause the spacecraft's purpose to be put into jeopardy depending on what communications were lost during the disruption. This behavior is different than Denial as this attack can also attempt to modify the data and messages as they are passed as a way to disrupt communications.
IMP-0003 Denial Measures designed to temporarily eliminate the use, access, or operation of a system for a period of time, usually without physical damage to the affected system. Threat actors may seek to deny ground controllers and other interested parties access to the victim spacecraft. This would be done exhausting system resource, degrading subsystems, or blocking communications entirely. This behavior is different from Disruption as this seeks to deny communications entirely, rather than stop them for a length of time.
IMP-0004 Degradation Measures designed to permanently impair (either partially or totally) the use of a system. Threat actors may target various subsystems or the hosted payload in such a way to rapidly increase it's degradation. This could potentially shorten the lifespan of the victim spacecraft.

Related SPARTA Countermeasures

ID Name Description D3FEND ISO 27001
CM0000 Countermeasure Not Identified This technique is a result of utilizing TTPs to create an impact and the applicable countermeasures are associated with the TTPs leveraged to achieve the impact None None
CM0049 Machine Learning Data Integrity When AI/ML is being used for mission critical operations, the integrity of the training data set is imperative. Data poisoning against the training data set can have detrimental effects on the functionality of the AI/ML. Fixing poisoned models is very difficult so model developers need to focus on countermeasures that could either block attack attempts or detect malicious inputs before the training cycle occurs. Regression testing over time, validity checking on data sets, manual analysis, as well as using statistical analysis to find potential injects can help detect anomalies. D3-PH D3-FE D3-DENCR D3-PA D3-FA A.8.4 A.5.10 A.5.14 A.8.20 A.8.26 A.5.10 A.5.33
CM0039 Least Privilege Employ the principle of least privilege, allowing only authorized processes which are necessary to accomplish assigned tasks in accordance with system functions. Ideally maintain a separate execution domain for each executing process. D3-MAC D3-EI D3-HBPI D3-KBPI D3-PSEP D3-MBT D3-PCSV D3-LFP D3-UBA A.5.16 A.5.18 A.8.2 A.5.15 A.8.2 A.8.18 A.8.19 A.8.19 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28
CM0069 Process White Listing Simple process ID whitelisting on the firmware level could impede attackers from instigating unnecessary processes which could impact the spacecraft D3-MAC D3-EAL D3-EDL A.8.19 A.8.19 A.5.8
CM0056 Data Backup Implement disaster recovery plans that contain procedures for taking regular data backups that can be used to restore critical data. Ensure backups are stored off system and is protected from common methods adversaries may use to gain access and destroy the backups to prevent recovery. D3-AI D3-DI D3-SYSM D3-DEM A.5.29 A.5.33 A.8.13 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28
CM0032 On-board Intrusion Detection & Prevention Utilize on-board intrusion detection/prevention system that monitors the mission critical components or systems and audit/logs actions. The IDS/IPS should have the capability to respond to threats (initial access, execution, persistence, evasion, exfiltration, etc.) and it should address signature-based attacks along with dynamic never-before seen attacks using machine learning/adaptive technologies. The IDS/IPS must integrate with traditional fault management to provide a wholistic approach to faults on-board the spacecraft. Spacecraft should select and execute safe countermeasures against cyber-attacks.  These countermeasures are a ready supply of options to triage against the specific types of attack and mission priorities. Minimally, the response should ensure vehicle safety and continued operations. Ideally, the goal is to trap the threat, convince the threat that it is successful, and trace and track the attacker — with or without ground support. This would support successful attribution and evolving countermeasures to mitigate the threat in the future. “Safe countermeasures” are those that are compatible with the system’s fault management system to avoid unintended effects or fratricide on the system. D3-FA D3-DA D3-FCR D3-FH D3-ID D3-IRA D3-HD D3-IAA D3-FHRA D3-NTA D3-PMAD D3-RTSD D3-ANAA D3-CA D3-CSPP D3-ISVA D3-PM D3-SDM D3-SFA D3-SFV D3-SICA D3-USICA D3-FBA D3-FEMC D3-FV D3-OSM D3-PFV D3-EHB D3-IDA D3-MBT D3-SBV D3-PA D3-PSMD D3-PSA D3-SEA D3-SSC D3-SCA D3-FAPA D3-IBCA D3-PCSV D3-FCA D3-PLA D3-UBA D3-RAPA D3-SDA D3-UDTA D3-UGLPA D3-ANET D3-AZET D3-JFAPA D3-LAM D3-NI D3-RRID D3-NTF D3-ITF D3-OTF D3-EI D3-EAL D3-EDL D3-HBPI D3-IOPR D3-KBPI D3-MAC D3-SCF A.8.15 A.8.15 A.8.6 A.8.17 A.5.33 A.8.15 A.8.15 A.5.29 A.5.25 A.5.26 A.5.27 A.5.8 A.5.7 A.8.12 A.8.7 A.8.16 A.8.16 A.8.16 A.8.16
CM0042 Robust Fault Management Ensure fault management system cannot be used against the spacecraft. Examples include: safe mode with crypto bypass, orbit correction maneuvers, affecting integrity of telemetry to cause action from ground, or some sort of proximity operation to cause spacecraft to go into safe mode. Understanding the safing procedures and ensuring they do not put the spacecraft in a more vulnerable state is key to building a resilient spacecraft. D3-AH D3-EHPV D3-PSEP D3-PH D3-SCP 7.5.1 7.5.2 7.5.3 A.5.2 A.5.29 A.8.1 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28
CM0044 Cyber-safe Mode Provide the capability to enter the spacecraft into a configuration-controlled and integrity-protected state representing a known, operational cyber-safe state (e.g., cyber-safe mode). Spacecraft should enter a cyber-safe mode when conditions that threaten the platform are detected.   Cyber-safe mode is an operating mode of a spacecraft during which all nonessential systems are shut down and the spacecraft is placed in a known good state using validated software and configuration settings. Within cyber-safe mode, authentication and encryption should still be enabled. The spacecraft should be capable of reconstituting firmware and software functions to pre-attack levels to allow for the recovery of functional capabilities. This can be performed by self-healing, or the healing can be aided from the ground. However, the spacecraft needs to have the capability to replan, based on equipment still available after a cyber-attack. The goal is for the spacecraft to resume full mission operations. If not possible, a reduced level of mission capability should be achieved. Cyber-safe mode software/configuration should be stored onboard the spacecraft in memory with hardware-based controls and should not be modifiable.                                                  D3-PH D3-EI D3-NI D3-BA 7.5.1 7.5.2 7.5.3 A.5.2 A.5.29 A.8.1 A.5.29 A.5.25 A.5.26 A.5.27 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28
CM0066 Model-based System Verification Real-time physics model-based system verification of state could help to verify data input and control sequence changes D3-OAM D3-AM D3-DEM D3-SVCDM D3-SYSDM A.8.16
CM0038 Segmentation Identify the key system components or capabilities that require isolation through physical or logical means. Information should not be allowed to flow between partitioned applications unless explicitly permitted by security policy. Isolate mission critical functionality from non-mission critical functionality by means of an isolation boundary (implemented via partitions) that controls access to and protects the integrity of, the hardware, software, and firmware that provides that functionality. Enforce approved authorizations for controlling the flow of information within the spacecraft and between interconnected systems based on the defined security policy that information does not leave the spacecraft boundary unless it is encrypted. Implement boundary protections to separate bus, communications, and payload components supporting their respective functions. D3-NI D3-BDI D3-NTF D3-ITF D3-OTF D3-EI D3-HBPI D3-KBPI D3-MAC D3-RRID D3-EAL D3-EDL D3-IOPR D3-SCF A.5.14 A.8.22 A.8.23 A.5.15 A.8.2 A.8.18 A.5.14 A.8.21 A.5.8 A.5.2 A.5.8 A.8.25 A.8.31 A.8.27 A.8.28
CM0048 Resilient Position, Navigation, and Timing If available, use an authentication mechanism that allows GNSS receivers to verify the authenticity of the GNSS information and of the entity transmitting it, to ensure that it comes from a trusted source. Have fault-tolerant authoritative time sourcing for the spacecraft's clock. The spacecraft should synchronize the internal system clocks for each processor to the authoritative time source when the time difference is greater than the FSW-defined interval. If Spacewire is utilized, then the spacecraft should adhere to mission-defined time synchronization standard/protocol to synchronize time across a Spacewire network with an accuracy around 1 microsecond. D3-MH D3-MAN 7.5.1 7.5.2 7.5.3 A.5.2 A.5.29 A.8.1 A.5.10 A.5.8 A.5.2 A.5.4 A.5.8 A.5.14 A.5.22 A.5.23 A.8.21