CM-5(6) - Access Restrictions for Change | Limit Library Privileges

Limit privileges to change software resident within software libraries.


Informational References

ISO 27001

ID: CM-5(6)
Enhancement of : CM-5

Countermeasures Covered by Control

ID Name Description D3FEND
CM0004 Development Environment Security In order to secure the development environment, the first step is understanding all the devices and people who interact with it. Maintain an accurate inventory of all people and assets that touch the development environment. Ensure strong multi-factor authentication is used across the development environment, especially for code repositories, as threat actors may attempt to sneak malicious code into software that's being built without being detected. Use zero-trust access controls to the code repositories where possible. For example, ensure the main branches in repositories are protected from injecting malicious code. A secure development environment requires change management, privilege management, auditing and in-depth monitoring across the environment. D3-AI D3-AVE D3-SWI D3-HCI D3-NNI D3-OAM D3-AM D3-OM D3-DI D3-MFA D3-CH D3-OTP D3-BAN D3-PA D3- FAPA D3- DQSA D3-IBCA D3-PCSV D3-PSMD
CM0010 Update Software Perform regular software updates to mitigate exploitation risk. Software updates may need to be scheduled around operational down times. Release updated versions of the software/firmware systems incorporating security-relevant updates, after suitable regression testing, at a frequency no greater than mission-defined frequency [i.e., 30 days]. Ideally old versions of software are removed after upgrading but restoration states (i.e., gold images) are recommended to remain on the system. D3-SU
CM0012 Software Bill of Materials Generate Software Bill of Materials (SBOM) against the entire software supply chain and cross correlate with known vulnerabilities (e.g., Common Vulnerabilities and Exposures) to mitigate known vulnerabilities. Protect the SBOM according to countermeasures in CM0001. D3-AI D3-AVE D3-SWI
CM0013 Dependency Confusion Ensure proper protections are in place for ensuring dependency confusion is mitigated like ensuring that internal dependencies be pulled from private repositories vice public repositories, ensuring that your CI/CD/development environment is secure as defined in CM0004 and validate dependency integrity by ensuring checksums match official packages. D3-LFP D3-UBA D3-RAPA D3-MAC
CM0015 Software Source Control Prohibit the use of binary or machine-executable code from sources with limited or no warranty and without the provision of source code. D3-PM D3-SBV D3-EI D3-EAL D3- EDL D3-DCE
CM0021 Software Digital Signature Prevent the installation of Flight Software without verification that the component has been digitally signed using a certificate that is recognized and approved by the mission. D3-CH D3-CBAN D3-FV D3-DLIC D3-EAL D3-SBV
CM0023 Configuration Management Use automated mechanisms to maintain and validate baseline configuration to ensure the spacecraft's is up-to-date, complete, accurate, and readily available. D3-ACH D3-CI D3-SICA D3-USICA

Space Threats Tagged by Control

ID Description

Sample Requirements

Requirement Rationale/Additional Guidance/Notes
The [organization] shall develop and document program-specific configuration management policies and procedures for the hardware and software for the spacecraft. {CM-1,CM-3,CM-5(6),SA-10,SA-10(3)}
The [organization] shall define processes and procedures to be followed when integrity verification tools detect unauthorized changes to software, firmware, and information.{SV-IT-2}{CM-3,CM-3(1),CM-3(5),CM-5(6),CM-6,CP-2,IR-6,IR-6(2),PM-30,SC-16(1),SC-51,SI-3,SI-4(7),SI-4(24),SI-7,SI-7(7),SI-7(10)}
The [organization] shall develop and document spacecraft integrity policies covering both hardware and software. {CM-5(6),SA-10(3),SI-1,SI-7(12)}
The [organization] shall enable integrity verification of software and firmware components.{SV-IT-2}{CM-3(5),CM-5(6),CM-10(1),SA-8(9),SA-8(11),SA-8(21),SA-10(1),SI-3,SI-4(24),SI-7,SI-7(10),SI-7(12),SR-4(4)} * The integrity verification mechanisms may include:  ** Stipulating and monitoring logical delivery of products and services, requiring downloading from approved, verification-enhanced sites; ** Encrypting elements (software, software patches, etc.) and supply chain process data in transit (motion) and at rest throughout delivery; ** Requiring suppliers to provide their elements “secure by default”, so that additional configuration is required to make the element insecure; ** Implementing software designs using programming languages and tools that reduce the likelihood of weaknesses; ** Implementing cryptographic hash verification; and ** Establishing performance and sub-element baseline for the system and system elements to help detect unauthorized tampering/modification during repairs/refurbishing. ** Stipulating and monitoring logical delivery of products and services, requiring downloading from approved, verification-enhanced sites; ** Encrypting elements (software, software patches, etc.) and supply chain process data in transit (motion) and at rest throughout delivery; ** Requiring suppliers to provide their elements “secure by default”, so that additional configuration is required to make the element insecure; ** Implementing software designs using programming languages and tools that reduce the likelihood of weaknesses; ** Implementing cryptographic hash verification; and ** Establishing performance and sub-element baseline for the system and system elements to help detect unauthorized tampering/modification during repairs/refurbishing.
The [spacecraft] shall employ the principle of least privilege, allowing only authorized accesses processes which are necessary to accomplish assigned tasks in accordance with system functions.{SV-AC-6}{AC-3,AC-6,AC-6(9),CA-9,CM-5,CM-5(5),CM-5(6),SA-8(2),SA-8(5),SA-8(6),SA-8(14),SA-8(23),SA-17(7),SC-2,SC-7(29),SC-32,SC-32(1),SI-3}

Related SPARTA Techniques and Sub-Techniques

ID Name Description
REC-0006 Gather FSW Development Information Threat actors may obtain information regarding the flight software (FSW) development environment for the victim spacecraft. This information may include the development environment, source code, compiled binaries, testing tools, and fault management.
REC-0006.01 Development Environment Threat actors may gather information regarding the development environment for the victim spacecraft's FSW. This information can include IDEs, configurations, source code, environment variables, source code repositories, code "secrets", and compiled binaries.
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.
IA-0001.01 Software Dependencies & Development Tools Threat actors may manipulate software dependencies (i.e. dependency confusion) and/or development tools prior to the customer receiving them in order to achieve data or system compromise. Software binaries and applications often depend on external software to function properly. spacecraft developers may use open source projects to help with their creation. These open source projects may be targeted by threat actors as a way to add malicious code to the victim spacecraft's dependencies.
IA-0001.02 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.
IA-0002 Compromise Software Defined Radio Threat actors may target software defined radios due to their software nature to establish C2 channels. Since SDRs are programmable, when combined with supply chain or development environment attacks, SDRs provide a pathway to setup covert C2 channels for a threat actor.
IA-0004 Secondary/Backup Communication Channel Threat actors may compromise alternative communication pathways which may not be as protected as the primary pathway. Depending on implementation the contingency communication pathways/solutions may lack the same level of security (i.e., physical security, encryption, authentication, etc.) which if forced to use could provide a threat actor an opportunity to launch attacks. Typically these would have to be coupled with other denial of service techniques on the primary pathway to force usage of secondary pathways.
IA-0004.02 Receiver Threat actors may target the backup/secondary receiver on the spacecraft as a method to inject malicious communications into the mission. The secondary receivers may come from different supply chains than the primary which could have different level of security and weaknesses. Similar to the ground station, the communication through the secondary receiver could be forced or happening naturally.
IA-0006 Compromise Hosted Payload Threat actors may compromise the target spacecraft hosted payload to initially access and/or persist within the system. Hosted payloads can usually be accessed from the ground via a specific command set. The command pathways can leverage the same ground infrastructure or some host payloads have their own ground infrastructure which can provide an access vector as well. Threat actors may be able to leverage the ability to command hosted payloads to upload files or modify memory addresses in order to compromise the system. Depending on the implementation, hosted payloads may provide some sort of lateral movement potential.
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.
IA-0007.01 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.
IA-0011 Auxiliary Device Compromise Threat actors may exploit the auxiliary/peripheral devices that get plugged into spacecrafts. It is no longer atypical to see spacecrafts, especially CubeSats, with Universal Serial Bus (USB) ports or other ports where auxiliary/peripheral devices can be plugged in. Threat actors can execute malicious code on the spacecrafts by copying the malicious code to auxiliary/peripheral devices and taking advantage of logic on the spacecraft to execute code on these devices. This may occur through manual manipulation of the auxiliary/peripheral devices, modification of standard IT systems used to initially format/create the auxiliary/peripheral device, or modification to the auxiliary/peripheral devices' firmware itself.
IA-0012 Assembly, Test, and Launch Operation Compromise Threat actors may target the spacecraft hardware and/or software while the spacecraft is at Assembly, Test, and Launch Operation (ATLO). ATLO is often the first time pieces of the spacecraft are fully integrated and exchanging data across interfaces. Malware could propagate from infected devices across the integrated spacecraft. For example, test equipment (i.e., transient cyber asset) is often brought in for testing elements of the spacecraft. Additionally, varying levels of physical security is in place which may be a reduction in physical security typically seen during development. The ATLO environment should be considered a viable attack vector and the appropriate/equivalent security controls from the primary development environment should be implemented during ATLO as well.
EX-0003 Modify Authentication Process Threat actors may modify the internal authentication process of the victim spacecraft to facilitate initial access, recurring execution, or prevent authorized entities from accessing the spacecraft. This can be done through the modification of the software binaries or memory manipulation techniques.
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-0008 Time Synchronized Execution Threat actors may develop payloads or insert malicious logic to be executed at a specific time.
EX-0008.01 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.
EX-0008.02 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.
EX-0009.01 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.
EX-0009.02 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-0009.03 Known Vulnerability (COTS/FOSS) Threat actors may utilize knowledge of the spacecraft software composition to enumerate and exploit known flaws or vulnerabilities in the commercial or open source software running on-board the target spacecraft.
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.
EX-0010.01 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.
EX-0010.02 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.
EX-0010.03 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.
EX-0010.04 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.
PER-0002.02 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).
DE-0007 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.
DE-0008 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.
LM-0001 Hosted Payload Threat actors may use the hosted payload within the victim spacecraft in order to gain access to other subsystems. The hosted payload often has a need to gather and send data to the internal subsystems, depending on its purpose. Threat actors may be able to take advantage of this communication in order to laterally move to the other subsystems and have commands be processed.
EXF-0006 Modify Communications Configuration Threat actors can manipulate communications equipment, modifying the existing software, hardware, or the transponder configuration to exfiltrate data via unintentional channels the mission has no control over.
EXF-0006.01 Software Defined Radio Threat actors may target software defined radios due to their software nature to setup exfiltration channels. Since SDRs are programmable, when combined with supply chain or development environment attacks, SDRs provide a pathway to setup covert exfiltration channels for a threat actor.
EXF-0006.02 Transponder Threat actors may change the transponder configuration to exfiltrate data via radio access to an attacker-controlled asset.
EXF-0008 Compromised Developer Site Threat actors may compromise development environments located within the ground system or a developer/partner site. This attack can take place in a number of different ways, including manipulation of source code, manipulating environment variables, or replacing compiled versions with a malicious one. This technique is usually performed before the target spacecraft is in orbit, with the hopes of adding malicious code to the actual FSW during the development process.