# SC-3(3) — Minimize Nonsecurity Functionality

- **Control ID:** SC-3(3)
- **Family:** [SC](/md/families/SC.md)
- **Baselines:** No content available.
- **Enhancement of:** [SC-3](/md/controls/SC-3.md)

## Description

Minimize the number of nonsecurity functions included within the isolation boundary containing security functions.

## Discussion

Where it is not feasible to achieve strict isolation of nonsecurity functions from security functions, it is necessary to take actions to minimize nonsecurity-relevant functions within the security function boundary. Nonsecurity functions contained within the isolation boundary are considered security-relevant because errors or malicious code in the software can directly impact the security functions of systems. The fundamental design objective is that the specific portions of systems that provide information security are of minimal size and complexity. Minimizing the number of nonsecurity functions in the security-relevant system components allows designers and implementers to focus only on those functions which are necessary to provide the desired security capability (typically access enforcement). By minimizing the nonsecurity functions within the isolation boundaries, the amount of code that is trusted to enforce security policies is significantly reduced, thus contributing to understandability.

## Implementation guidance

No content available.

## CSF 2.0 subcategories

No content available.

## Related controls

No content available.

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Derived from official NIST publications (NIST SP 800-53 Rev 5 and NIST CSF 2.0). nistcontrols.com is not affiliated with NIST.