AC-22 Publicly Accessible Content
High-Level Description
Family: Access Control (AC) Framework: NIST SP 800-53 Rev 5
In accordance with applicable laws, executive orders, directives, policies, regulations, standards, and guidelines, the public is not authorized to have access to nonpublic information, including information protected under the PRIVACT and proprietary information. Publicly accessible content addresses systems that are controlled by the organization and accessible to the public, typically without identification or authentication. Posting information on non-organizational systems (e.g., non-organizational public websites, forums, and social media) is covered by organizational policy. While organizations may have individuals who are responsible for developing and implementing policies about the information that can be made publicly accessible, publicly accessible content addresses the management of the individuals who make such information publicly accessible.
What to Check
- Verify AC-22 Publicly Accessible Content is documented in SSP
- Validate all 4 control requirements are implemented
- Confirm control is operating effectively
- Review evidence of continuous monitoring for AC-22
How to Test
Step 1: Review Documentation
Examine the System Security Plan (SSP) and related artifacts for AC-22 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 IAM policies and access controls | cloud_audit_iam_policies |
| hackbrowser | Test web application access controls | hackbrowser |
Remediation Guide
Control Statement
Designate individuals authorized to make information publicly accessible; Train authorized individuals to ensure that publicly accessible information does not contain nonpublic information; Review the proposed content of information prior to posting onto the publicly accessible system to ensure that nonpublic information is not included; and Review the content on the publicly accessible system for nonpublic information [organization-defined] and remove such information, if discovered.
Implementation Guidance
In accordance with applicable laws, executive orders, directives, policies, regulations, standards, and guidelines, the public is not authorized to have access to nonpublic information, including information protected under the PRIVACT and proprietary information. Publicly accessible content addresses systems that are controlled by the organization and accessible to the public, typically without identification or authentication. Posting information on non-organizational systems (e.g., non-organizational public websites, forums, and social media) is covered by organizational policy. While organizations may have individuals who are responsible for developing and implementing policies about the information that can be made publicly accessible, publicly accessible content addresses the management of the individuals who make such information publicly accessible.
Risk Assessment
| Finding | Severity | Impact |
|---|---|---|
| AC-22 Publicly Accessible Content not implemented | High | Access Control |
| AC-22 partially implemented | Medium | Incomplete Access Control |
CWE Categories
| CWE ID | Title |
|---|---|
| CWE-284 | Improper Access Control |
References
- NIST SP 800-53 Rev 5 - AC-22
- 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 (AC-3, AT-2, AT-3, AU-13) reviewed