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SA-8(16)_self-reliant-trustworthiness

DevOps & Security
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Implement the security design principle of self-reliant trustworthiness in [organization-defined].

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/NIST/SP800-53_rev5/SA_system-and-services-acquisition/SA-8(16)_self-reliant-trustworthiness/SKILL.md

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SA-8(16) Self-reliant Trustworthiness

Enhancement of: SA-8

High-Level Description

Family: System and Services Acquisition (SA) Framework: NIST SP 800-53 Rev 5

The principle of self-reliant trustworthiness states that systems minimize their reliance on other systems for their own trustworthiness. A system is trustworthy by default, and any connection to an external entity is used to supplement its function. If a system were required to maintain a connection with another external entity in order to maintain its trustworthiness, then that system would be vulnerable to malicious and non-malicious threats that could result in the loss or degradation of that connection. The benefit of the principle of self-reliant trustworthiness is that the isolation of a system will make it less vulnerable to attack. A corollary to this principle relates to the ability of the system (or system component) to operate in isolation and then resynchronize with other components when it is rejoined with them.

What to Check

  • Verify SA-8(16) Self-reliant Trustworthiness is documented in SSP
  • Confirm control is operating effectively
  • Review evidence of continuous monitoring for SA-8(16)
  • Verify enhancement builds upon base control SA-8

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SA-8(16) implementation details. Verify the organization has documented how this control is satisfied.

Step 2: Validate Implementation

# For cloud environments, use cloud-audit-mcp tools
# For on-premises, review system configurations directly

# Example: Check if account management policies exist
grep -r "account.management\|access.control" /etc/security/ 2>/dev/null

Step 3: Test Operating Effectiveness

Verify the control is actively functioning, not just documented. Check logs, configurations, and operational evidence.

Tools

ToolPurposeUsage
Manual ReviewDocumentation and interview-basedN/A

Remediation Guide

Control Statement

Implement the security design principle of self-reliant trustworthiness in [organization-defined].

Implementation Guidance

The principle of self-reliant trustworthiness states that systems minimize their reliance on other systems for their own trustworthiness. A system is trustworthy by default, and any connection to an external entity is used to supplement its function. If a system were required to maintain a connection with another external entity in order to maintain its trustworthiness, then that system would be vulnerable to malicious and non-malicious threats that could result in the loss or degradation of that connection. The benefit of the principle of self-reliant trustworthiness is that the isolation of a system will make it less vulnerable to attack. A corollary to this principle relates to the ability of the system (or system component) to operate in isolation and then resynchronize with other components when it is rejoined with them.

Risk Assessment

FindingSeverityImpact
SA-8(16) Self-reliant Trustworthiness not implementedMediumSystem and Services Acquisition
SA-8(16) partially implementedLowIncomplete System and Services Acquisition

CWE Categories

CWE IDTitle
CWE-16Configuration

References

Checklist

  • Control documented in SSP
  • Implementation evidence collected
  • Operating effectiveness validated
  • Continuous monitoring in place
  • Related controls (none) reviewed