NIST · Shared reference library

NIST SP 800-53 Rev. 5 Common Control Library

Browse 1,193 controls and enhancements across 20 security and privacy families. Use the GovRAMP crosswalk to locate controls referenced by Security Snapshot, Core, and Moderate.

A shared catalog supports common-control planning; designation as a common, hybrid, or system-specific control depends on your organization’s implementation and inheritance decisions.

Sources and crosswalk scope

NIST OSCAL content 5.1.1+u4, retrieved 2026-09-18. GovRAMP Snapshot v1.4 and Core selection from Moderate v1.06 reference the December 2020 Rev. 5 text. Mappings establish exact identifier correspondence, not identical requirements, inherited implementation, or GovRAMP authorization. GovRAMP parameters and additional requirements remain authoritative for each program. Full Moderate, High, and other programs are not mapped here. Withdrawn controls are retained for reference.

Official pinned NIST source

SHA-256: 81cf2de45ede9aef3de7ce09d65ea9d32f662c483bbf916f6e346292b22f7763

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3 matching controls · Page 1 of 1

Access Control · Base control

AC-21 · Information Sharing

Control statement and discussion

NIST control statement

a. Enable authorized users to determine whether access authorizations assigned to a sharing partner match the information’s access and use restrictions for [Assignment: information-sharing circumstances] ; and b. Employ [Assignment: automated mechanisms] to assist users in making information sharing and collaboration decisions.

Discussion

Information sharing applies to information that may be restricted in some manner based on some formal or administrative determination. Examples of such information include, contract-sensitive information, classified information related to special access programs or compartments, privileged information, proprietary information, and personally identifiable information. Security and privacy risk assessments as well as applicable laws, regulations, and policies can provide useful inputs to these determinations. Depending on the circumstances, sharing partners may be defined at the individual, group, or organizational level. Information may be defined by content, type, security category, or special access program or compartment. Access restrictions may include non-disclosure agreements (NDA). Information flow techniques and security attributes may be used to provide automated assistance to users making sharing and collaboration decisions.

GovRAMP crosswalk

Access Control · Enhancement

AC-21(1) · Automated Decision Support

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Control statement and discussion

NIST control statement

Employ [Assignment: automated mechanisms] to enforce information-sharing decisions by authorized users based on access authorizations of sharing partners and access restrictions on information to be shared.

Discussion

Automated mechanisms are used to enforce information sharing decisions.

GovRAMP crosswalk

Not selected in the imported Snapshot or Core sets. This does not establish exclusion from other GovRAMP baselines.

Access Control · Enhancement

AC-21(2) · Information Search and Retrieval

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Control statement and discussion

NIST control statement

Implement information search and retrieval services that enforce [Assignment: information-sharing restrictions].

Discussion

Information search and retrieval services identify information system resources relevant to an information need.

GovRAMP crosswalk

Not selected in the imported Snapshot or Core sets. This does not establish exclusion from other GovRAMP baselines.