# SI-21 — Information Refresh

- **Control ID:** SI-21
- **Family:** [SI](/md/families/SI.md)
- **Baselines:** No content available.
- **Enhancement of:** No content available.

## Description

Refresh \[assignment\] at \[assignment\] or generate the information on demand and delete the information when no longer needed.

## Discussion

Retaining information for longer than it is needed makes it an increasingly valuable and enticing target for adversaries. Keeping information available for the minimum period of time needed to support organizational missions or business functions reduces the opportunity for adversaries to compromise, capture, and exfiltrate that information.

## Implementation guidance

No content available.

## CSF 2.0 subcategories

No content available.

## Related controls

- [SI-14](/md/controls/SI-14.md)

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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.