SC 29 Heterogeneity

---
name: "SC-29_heterogeneity"
description: "Employ a diverse set of information technologies for the following system components in the implementation of the system: [organization-defined]."
category: "configuration"
version: "5.2.0"
author: "cyberstrike-official"
tags:
  - nist
  - sp800-53
  - rev5
  - sc-29
  - sc
tech_stack:
  - aws
  - azure
  - gcp
  - linux
  - windows
  - network
cwe_ids:
  - CWE-311
chains_with:
  - AU-9
  - PL-8
  - SC-27
  - SC-30
  - SR-3
prerequisites: []
severity_boost:
  AU-9: "Chain with AU-9 for comprehensive security coverage"
  PL-8: "Chain with PL-8 for comprehensive security coverage"
  SC-27: "Chain with SC-27 for comprehensive security coverage"
---

# SC-29 Heterogeneity

## High-Level Description

**Family:** System and Communications Protection (SC)
**Framework:** NIST SP 800-53 Rev 5

Increasing the diversity of information technologies within organizational systems reduces the impact of potential exploitations or compromises of specific technologies. Such diversity protects against common mode failures, including those failures induced by supply chain attacks. Diversity in information technologies also reduces the likelihood that the means adversaries use to compromise one system component will be effective against other system components, thus further increasing the adversary work factor to successfully complete planned attacks. An increase in diversity may add complexity and management overhead that could ultimately lead to mistakes and unauthorized configurations.

## What to Check

- [ ] Verify SC-29 Heterogeneity is documented in SSP
- [ ] Confirm control is operating effectively
- [ ] Review evidence of continuous monitoring for SC-29

## How to Test

### Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SC-29 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

| Tool            | Purpose                               | Usage                                |
| --------------- | ------------------------------------- | ------------------------------------ |
| cloud-audit-mcp | Check encryption and network controls | `cloud_audit_encryption`             |
| nmap            | Network scanning                      | `nmap -sV --script ssl-enum-ciphers` |

## Remediation Guide

### Control Statement

Employ a diverse set of information technologies for the following system components in the implementation of the system: [organization-defined].

### Implementation Guidance

Increasing the diversity of information technologies within organizational systems reduces the impact of potential exploitations or compromises of specific technologies. Such diversity protects against common mode failures, including those failures induced by supply chain attacks. Diversity in information technologies also reduces the likelihood that the means adversaries use to compromise one system component will be effective against other system components, thus further increasing the adversary work factor to successfully complete planned attacks. An increase in diversity may add complexity and management overhead that could ultimately lead to mistakes and unauthorized configurations.

## Risk Assessment

| Finding                             | Severity | Impact                                          |
| ----------------------------------- | -------- | ----------------------------------------------- |
| SC-29 Heterogeneity not implemented | High     | System and Communications Protection            |
| SC-29 partially implemented         | Medium   | Incomplete System and Communications Protection |

## CWE Categories

| CWE ID  | Title                                |
| ------- | ------------------------------------ |
| CWE-311 | Missing Encryption of Sensitive Data |

## References

- [NIST SP 800-53 Rev 5 - SC-29](https://csrc.nist.gov/projects/cprt/catalog#/cprt/framework/version/SP_800_53_5_1_1/home?element=sc-29)
- [NIST SP 800-53A Rev 5 (Assessment Procedures)](https://csrc.nist.gov/pubs/sp/800/53/a/r5/final)
- [NIST SP 800-53 Rev 5 Full Catalog](https://csrc.nist.gov/pubs/sp/800/53/r5/upd1/final)

## Checklist

- [ ] Control documented in SSP
- [ ] Implementation evidence collected
- [ ] Operating effectiveness validated
- [ ] Continuous monitoring in place
- [ ] Related controls (AU-9, PL-8, SC-27, SC-30, SR-3) reviewed