Dynamic Analysis

Employ dynamic analysis (e.g., using simulation, penetration testing, fuzzing, etc.) to identify software/firmware weaknesses and vulnerabilities in developed and incorporated code (open source, commercial, or third-party developed code). Testing should occur (1) on potential system elements before acceptance; (2) as a realistic simulation of known adversary tactics, techniques, procedures (TTPs), and tools; and (3) throughout the lifecycle on physical and logical systems, elements, and processes. FLATSATs as well as digital twins can be used to perform the dynamic analysis depending on the TTPs being executed. Digital twins via instruction set simulation (i.e., emulation) can provide robust environment for dynamic analysis and TTP execution.

Best Segment for Countermeasure Deployment

  • Ground Segment and Development Environment

NIST Rev5 Controls

D3FEND Techniques

D3FEND Artifacts

ISO 27001

ID: CM0018
NASA Best Practice Guide:  MI-AUTH-01 | MI-AUTH-02 | MI-INTG-01 | MI-DCO-02
ESA Space Shield Mitigation:  M2039
Created: 2022/10/19
Last Modified: 2023/11/29

Techniques Addressed by Countermeasure

ID Name Description
IA-0001 Compromise Supply Chain Threat actors may manipulate or compromise products or product delivery mechanisms before the customer receives them in order to achieve data or system compromise.
.02 Software Supply Chain Threat actors may manipulate software binaries and applications prior to the customer receiving them in order to achieve data or system compromise. This attack can take place in a number of ways, including manipulation of source code, manipulation of the update and/or distribution mechanism, or replacing compiled versions with a malicious one.
.03 Hardware Supply Chain Threat actors may manipulate hardware components in the victim spacecraft prior to the customer receiving them in order to achieve data or system compromise. The threat actor can insert backdoors and give them a high level of control over the system when they modify the hardware or firmware in the supply chain. This would include ASIC and FPGA devices as well. A spacecraft component can also be damaged if a specific HW component, built to fail after a specific period, or counterfeit with a low reliability, breaks out.
IA-0007 Compromise Ground System Threat actors may initially compromise the ground system in order to access the target spacecraft. 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. Threat actors may also perform further reconnaissance within the system to enumerate mission networks and gather information related to ground station logical topology, missions ran out of said ground station, birds that are in-band of targeted ground stations, and other mission system capabilities.
.01 Compromise On-Orbit Update Threat actors may manipulate and modify on-orbit updates before they are sent to the target spacecraft. 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.
EX-0004 Compromise Boot Memory Threat actors may manipulate boot memory in order to execute malicious code, bypass internal processes, or DoS the system. This technique can be used to perform other tactics such as Defense Evasion.
EX-0005 Exploit Hardware/Firmware Corruption Threat actors can target the underlying hardware and/or firmware using various TTPs that will be dependent on the specific hardware/firmware. Typically, software tools (e.g., antivirus, antimalware, intrusion detection) can protect a system from threat actors attempting to take advantage of those vulnerabilities to inject malicious code. However, there exist security gaps that cannot be closed by the above-mentioned software tools since they are not stationed on software applications, drivers or the operating system but rather on the hardware itself. Hardware components, like memory modules and caches, can be exploited under specific circumstances thus enabling backdoor access to potential threat actors. In addition to hardware, the firmware itself which often is thought to be software in its own right also provides an attack surface for threat actors. Firmware is programming that's written to a hardware device's non-volatile memory where the content is saved when a hardware device is turned off or loses its external power source. Firmware is written directly onto a piece of hardware during manufacturing and it is used to run on the device and can be thought of as the software that enables hardware to run. In the space vehicle context, firmware and field programmable gate array (FPGA)/application-specific integrated circuit (ASIC) logic/code is considered equivalent to firmware.
.01 Design Flaws Threat actors may target design features/flaws with the hardware design to their advantage to cause the desired impact. Threat actors may utilize the inherent design of the hardware (e.g. hardware timers, hardware interrupts, memory cells), which is intended to provide reliability, to their advantage to degrade other aspects like availability. Additionally, field programmable gate array (FPGA)/application-specific integrated circuit (ASIC) logic can be exploited just like software code can be exploited. There could be logic/design flaws embedded in the hardware (i.e., FPGA/ASIC) which may be exploitable by a threat actor.
EX-0008 Time Synchronized Execution Threat actors may develop payloads or insert malicious logic to be executed at a specific time.
.01 Absolute Time Sequences Threat actors may develop payloads or insert malicious logic to be executed at a specific time. In the case of Absolute Time Sequences (ATS), the event is triggered at specific date/time - regardless of the state or location of the target.
.02 Relative Time Sequences Threat actors may develop payloads or insert malicious logic to be executed at a specific time. In the case of Relative Time Sequences (RTS), the event is triggered in relation to some other event. For example, a specific amount of time after boot.
EX-0009 Exploit Code Flaws Threats actors may identify and exploit flaws or weaknesses within the software running on-board the target spacecraft. These attacks may be extremely targeted and tailored to specific coding errors introduced as a result of poor coding practices or they may target known issues in the commercial software components.
.01 Flight Software Threat actors may abuse known or unknown flight software code flaws in order to further the attack campaign. Some FSW suites contain API functionality for operator interaction. Threat actors may seek to exploit these or abuse a vulnerability/misconfiguration to maliciously execute code or commands. In some cases, these code flaws can perpetuate throughout the victim spacecraft, allowing access to otherwise segmented subsystems.
.02 Operating System Threat actors may exploit flaws in the operating system code, which controls the storage, memory management, provides resources to the FSW, and controls the bus. There has been a trend where some modern spacecraft are running Unix-based operating systems and establishing SSH connections for communications between the ground and spacecraft. Threat actors may seek to gain access to command line interfaces & shell environments in these instances. Additionally, most operating systems, including real-time operating systems, include API functionality for operator interaction. Threat actors may seek to exploit these or abuse a vulnerability/misconfiguration to maliciously execute code or commands.
EX-0010 Malicious Code Threat actors may rely on other tactics and techniques in order to execute malicious code on the victim spacecraft. This can be done via compromising the supply chain or development environment in some capacity or taking advantage of known commands. However, once malicious code has been uploaded to the victim spacecraft, the threat actor can then trigger the code to run via a specific command or wait for a legitimate user to trigger it accidently. The code itself can do a number of different things to the hosted payload, subsystems, or underlying OS.
.01 Ransomware Threat actors may encrypt spacecraft data to interrupt availability and usability. Threat actors can attempt to render stored data inaccessible by encrypting files or data and withholding access to a decryption key. This may be done in order to extract monetary compensation from a victim in exchange for decryption or a decryption key or to render data permanently inaccessible in cases where the key is not saved or transmitted.
.02 Wiper Malware Threat actors may deploy wiper malware, which is a type of malicious software designed to destroy data or render it unusable. Wiper malware can spread through various means, software vulnerabilities (CWE/CVE), or by exploiting weak or stolen credentials.
.03 Rootkit Rootkits are programs that hide the existence of malware by intercepting/hooking and modifying operating system API calls that supply system information. Rootkits or rootkit enabling functionality may reside at the flight software or kernel level in the operating system or lower, to include a hypervisor, Master Boot Record, or System Firmware.
.04 Bootkit Adversaries may use bootkits to persist on systems and evade detection. Bootkits reside at a layer below the operating system and may make it difficult to perform full remediation unless an organization suspects one was used and can act accordingly.
PER-0001 Memory Compromise Threat actors may manipulate memory (boot, RAM, etc.) in order for their malicious code and/or commands to remain on the victim spacecraft. The spacecraft may have mechanisms that allow for the automatic running of programs on system reboot, entering or returning to/from safe mode, or during specific events. Threat actors may target these specific memory locations in order to store their malicious code or file, ensuring that the attack remains on the system even after a reset.
PER-0002 Backdoor Threat actors may find and target various backdoors, or inject their own, within the victim spacecraft in the hopes of maintaining their attack.
.01 Hardware Threat actors may find and target various hardware backdoors within the victim spacecraft in the hopes of maintaining their attack. Once in orbit, mitigating the risk of various hardware backdoors becomes increasingly difficult for ground controllers. By targeting these specific vulnerabilities, threat actors are more likely to remain persistent on the victim spacecraft and perpetuate further attacks.
.02 Software Threat actors may inject code to create their own backdoor to establish persistent access to the spacecraft. This may be done through modification of code throughout the software supply chain or through modification of the software-defined radio configuration (if applicable).

Space Threats Addressed by Countermeasure

ID Description
SV-MA-3 Attacks on critical software subsystems   Attitude Determination and Control (AD&C) subsystem determines and controls the orientation of the satellite. Any cyberattack that could disrupt some portion of the control loop - sensor data, computation of control commands, and receipt of the commands would impact operations   Telemetry, Tracking and Commanding (TT&C) subsystem provides interface between satellite and ground system. Computations occur within the RF portion of the TT&C subsystem, presenting cyberattack vector   Command and Data Handling (C&DH) subsystem is the brains of the satellite. It interfaces with other subsystems, the payload, and the ground. It receives, validate, decodes, and sends commands to other subsystems, and it receives, processes, formats, and routes data for both the ground and onboard computer. C&DH has the most cyber content and is likely the biggest target for cyberattack.   Electrical Power Subsystem (EPS) provides, stores, distributes, and controls power on the satellite. An attack on EPS could disrupt, damage, or destroy the satellite.  
SV-SP-1 Exploitation of software vulnerabilities (bugs); Unsecure code, logic errors, etc. in the FSW.  
SV-SP-3 Introduction of malicious software such as a virus, worm, Distributed Denial-Of-Service (DDOS) agent, keylogger, rootkit, or Trojan Horse  
SV-SP-6 Software reuse, COTS dependence, and standardization of onboard systems using building block approach with addition of open-source technology leads to supply chain threat  
SV-SP-9 On-orbit software updates/upgrades/patches/direct memory writes. If TT&C is compromised or MOC or even the developer's environment, the risk exists to do a variation of a supply chain attack where after it is in orbit you inject malicious code  
SV-SP-10 Compromise development environment source code (applicable to development environments not covered by threat SV-SP-1, SV-SP-3, and SV-SP-4).  
SV-SP-2 Testing only focuses on functional requirements and rarely considers end to end or abuse cases  
SV-SP-5 Hardware failure (i.e., tainted hardware) {ASIC and FPGA focused}