SI-23_information-fragmentation

SI-23 Information Fragmentation

High-Level Description

Family: System and Information Integrity (SI) Framework: NIST SP 800-53 Rev 5

One objective of the advanced persistent threat is to exfiltrate valuable information. Once exfiltrated, there is generally no way for the organization to recover the lost information. Therefore, organizations may consider dividing the information into disparate elements and distributing those elements across multiple systems or system components and locations. Such actions will increase the adversary’s work factor to capture and exfiltrate the desired information and, in so doing, increase the probability of detection. The fragmentation of information impacts the organization’s ability to access the information in a timely manner. The extent of the fragmentation is dictated by the impact or classification level (and value) of the information, threat intelligence information received, and whether data tainting is used (i.e., data tainting-derived information about the exfiltration of some information could result in the fragmentation of the remaining information).

What to Check

• Verify SI-23 Information Fragmentation is documented in SSP
• Validate all 2 control requirements are implemented
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SI-23

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SI-23 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

Remediation Guide

Control Statement

Based on [organization-defined]: Fragment the following information: [organization-defined] ; and Distribute the fragmented information across the following systems or system components: [organization-defined].

Implementation Guidance

One objective of the advanced persistent threat is to exfiltrate valuable information. Once exfiltrated, there is generally no way for the organization to recover the lost information. Therefore, organizations may consider dividing the information into disparate elements and distributing those elements across multiple systems or system components and locations. Such actions will increase the adversary’s work factor to capture and exfiltrate the desired information and, in so doing, increase the probability of detection. The fragmentation of information impacts the organization’s ability to access the information in a timely manner. The extent of the fragmentation is dictated by the impact or classification level (and value) of the information, threat intelligence information received, and whether data tainting is used (i.e., data tainting-derived information about the exfiltration of some information could result in the fragmentation of the remaining information).

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - SI-23
• NIST SP 800-53A Rev 5 (Assessment Procedures)
• NIST SP 800-53 Rev 5 Full Catalog

Checklist

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