AC-3(15)_discretionary-and-mandatory-access-control
DevOps & SecurityEnforce [organization-defined] over the set of covered subjects and objects specified in the policy;
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AC-3(15) Discretionary and Mandatory Access Control
Enhancement of: AC-3
High-Level Description
Family: Access Control (AC) Framework: NIST SP 800-53 Rev 5
Simultaneously implementing a mandatory access control policy and a discretionary access control policy can provide additional protection against the unauthorized execution of code by users or processes acting on behalf of users. This helps prevent a single compromised user or process from compromising the entire system.
What to Check
- Verify AC-3(15) Discretionary and Mandatory Access Control is documented in SSP
- Validate all 2 control requirements are implemented
- Confirm control is operating effectively
- Review evidence of continuous monitoring for AC-3(15)
- Verify enhancement builds upon base control AC-3
How to Test
Step 1: Review Documentation
Examine the System Security Plan (SSP) and related artifacts for AC-3(15) 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-mcp | Test web application access controls | browser_auth_test |
Remediation Guide
Control Statement
Enforce [organization-defined] over the set of covered subjects and objects specified in the policy; and Enforce [organization-defined] over the set of covered subjects and objects specified in the policy.
Implementation Guidance
Simultaneously implementing a mandatory access control policy and a discretionary access control policy can provide additional protection against the unauthorized execution of code by users or processes acting on behalf of users. This helps prevent a single compromised user or process from compromising the entire system.
Risk Assessment
| Finding | Severity | Impact |
|---|---|---|
| AC-3(15) Discretionary and Mandatory Access Control not implemented | High | Access Control |
| AC-3(15) partially implemented | Medium | Incomplete Access Control |
CWE Categories
| CWE ID | Title |
|---|---|
| CWE-284 | Improper Access Control |
References
- NIST SP 800-53 Rev 5 - AC-3(15)
- 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 (SC-2, SC-3, AC-4) reviewed