Trusted Components

LOW MODERATE HIGH

1 Overlay 0 Related Controls

Requirements NIST SOURCE

Implement the security design principle of trusted components in [systems or system components].

Discussion (NIST Supplemental Guidance)

The principle of trusted components states that a component is trustworthy to at least a level commensurate with the security dependencies it supports (i.e., how much it is trusted to perform its security functions by other components). This principle enables the composition of components such that trustworthiness is not inadvertently diminished and the trust is not consequently misplaced. Ultimately, this principle demands some metric by which the trust in a component and the trustworthiness of a component can be measured on the same abstract scale. The principle of trusted components is particularly relevant when considering systems and components in which there are complex chains of trust dependencies. A trust dependency is also referred to as a trust relationship and there may be chains of trust relationships. The principle of trusted components also applies to a compound component that consists of subcomponents (e.g., a subsystem), which may have varying levels of trustworthiness. The conservative assumption is that the trustworthiness of a compound component is that of its least trustworthy subcomponent. It may be possible to provide a security engineering rationale that the trustworthiness of a particular compound component is greater than the conservative assumption. However, any such rationale reflects logical reasoning based on a clear statement of the trustworthiness objectives as well as relevant and credible evidence. The trustworthiness of a compound component is not the same as increased application of defense-in-depth layering within the component or a replication of components. Defense-in-depth techniques do not increase the trustworthiness of the whole above that of the least trustworthy component.

Implementation Guidance

Engineering Interpretation

Original engineering commentary written for this explorer — not NIST source text and not authoritative guidance.

No engineering interpretation has been authored for SA-8(9) yet. This section is architected to receive it — see the Requirements and Assessment sections above for the authoritative NIST source content in the meantime.

Assessment

NIST SP 800-53A REV 5.2.0

Assessment Objectives

systems or system components that implement the security design principle of trusted components are defined;
<SA-08(09)_ODP systems or system components> implement the security design principle of trusted components.

Examine

[SELECT FROM: Supply chain risk management plan; system and services acquisition policy; procedures addressing the security design principle of trusted components used in the specification, design, development, implementation, and modification of the system; system design documentation; security, supply chain risk management, and privacy requirements and specifications for the system; system security and privacy architecture; procedures for determining component assurance; system security plan; other relevant documents or records].

Interview

[SELECT FROM: Organizational personnel with the responsibility for determining system security and privacy requirements; organizational personnel with system specification, design, development, implementation, and modification responsibilities; system developers; organizational personnel with information security responsibilities; organizational personnel with supply chain risk management responsibilities].

Test

[SELECT FROM: Organizational processes for applying the security design principle of trusted components in system specification, design, development, implementation, and modification; mechanisms supporting the application of the security design principle of trusted components in system specification, design, development, implementation, and modification].

Overlays

Showing the OT/ICS overlay for the parent control SA-8 — see the SA-8(9) entries within each baseline below.

OT/ICS Overlay SP 800-82r3

NIST SP 800-82r3 Appendix F, Table 22. Blank baseline means the control/control enhancement is not selected in that initial OT baseline.

LOW

Base control: Included (matches standard baseline)

MODERATE

Base control: Included (matches standard baseline)

HIGH

Base control: Included (matches standard baseline)

STIGs & CCIs

No STIG checks or CCI mappings are currently loaded for SA-8(9). This section is architected to display, per product: STIG ID, Finding ID, Severity, Title, Description, Check, Fix, CCI, and NIST control mapping — but nothing is populated here until a real DISA STIG/CCI dataset is ingested.

Learn more about STIG/CCI integration →

Evidence

Potential Evidence — Derived

Categorized from the SP 800-53A "Examine"/"Test" artifact list above by keyword — not an authoritative NIST evidence list.

Policy

Supply chain risk management plan
system and services acquisition policy
system security plan

Configuration

system design documentation
system security and privacy architecture

Testing

Organizational processes for applying the security design principle of trusted components in system specification, design, development, implementation, and modification
mechanisms supporting the application of the security design principle of trusted components in system specification, design, development, implementation, and modification

Other Records

procedures addressing the security design principle of trusted components used in the specification, design, development, implementation, and modification of the system
security, supply chain risk management, and privacy requirements and specifications for the system
procedures for determining component assurance
other relevant documents or records