System Call

A system call is the programmatic way in which a computer program requests a service from the kernel of the operating system it is executed on. This may include hardware-related services (for example, accessing a hard disk drive), creation and execution of new processes, and communication with integral kernel services such as process scheduling. System calls provide an essential interface between a process and the operating system.

ID: d3f:SystemCall

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Type: Top Level Artifacts

Informational References

https://d3fend.mitre.org/dao/artifact/d3f:SystemCall/

D3FEND Techniques

Name	Description
D3-PA	Process Analysis consists of observing a running application process and analyzing it to watch for certain behaviors or conditions which may indicate adversary activity. Analysis can occur inside of the process or through a third-party monitoring application. Examples include monitoring system and privileged calls, monitoring process initiation chains, and memory boundary allocations.
D3-SCA	Analyzing system calls to determine whether a process is exhibiting unauthorized behavior.
D3-EI	Execution Isolation techniques prevent application processes from accessing non-essential system resources, such as memory, devices, or files.
D3-KBPI	Using kernel-level capabilities to isolate processes.
D3-SCF	Configuring a kernel to use an allow or deny list to filter kernel api calls.

SPARTA Countermeasures

ID	Name	Description
CM0040	Shared Resource Leakage	Prevent unauthorized and unintended information transfer via shared system resources. Ensure that processes reusing a shared system resource (e.g., registers, main memory, secondary storage) do not have access to information (including encrypted representations of information) previously stored in that resource during a prior use by a process after formal release of that resource back to the system or reuse
CM0047	Operating System Security	Ensure spacecraft's operating system is scrutinized/whitelisted and has received adequate software assurance previously. The operating system should be analyzed for its attack surface and non-utilized features should be stripped from the operating system. Many real-time operating systems contain features that are not necessary for spacecraft operations and only increase the attack surface.
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.
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.
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.