# AC-11(1)_pattern-hiding-displays

> Conceal, via the device lock, information previously visible on the display with a publicly viewable image.

- Skill: `cyberstrikeus/ac-11-1-pattern-hiding-displays` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/ac-11-1-pattern-hiding-displays`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/ac-11-1-pattern-hiding-displays/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: cyberstrikeus (https://skillmd.com/u/cyberstrikeus)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/cyberstrikeus/ac-11-1-pattern-hiding-displays

---


# AC-11(1) Pattern-hiding Displays

> **Enhancement of:** AC-11

## High-Level Description

**Family:** Access Control (AC)
**Framework:** NIST SP 800-53 Rev 5

The pattern-hiding display can include static or dynamic images, such as patterns used with screen savers, photographic images, solid colors, clock, battery life indicator, or a blank screen with the caveat that controlled unclassified information is not displayed.

## What to Check

- [ ] Verify AC-11(1) Pattern-hiding Displays is documented in SSP
- [ ] Confirm control is operating effectively
- [ ] Review evidence of continuous monitoring for AC-11(1)
- [ ] Verify enhancement builds upon base control AC-11

## How to Test

### Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for AC-11(1) 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

Conceal, via the device lock, information previously visible on the display with a publicly viewable image.

### Implementation Guidance

The pattern-hiding display can include static or dynamic images, such as patterns used with screen savers, photographic images, solid colors, clock, battery life indicator, or a blank screen with the caveat that controlled unclassified information is not displayed.

## Risk Assessment

| Finding                                          | Severity | Impact                    |
| ------------------------------------------------ | -------- | ------------------------- |
| AC-11(1) Pattern-hiding Displays not implemented | High     | Access Control            |
| AC-11(1) partially implemented                   | Medium   | Incomplete Access Control |

## CWE Categories

| CWE ID  | Title                   |
| ------- | ----------------------- |
| CWE-284 | Improper Access Control |

## References

- [NIST SP 800-53 Rev 5 - AC-11(1)](https://csrc.nist.gov/projects/cprt/catalog#/cprt/framework/version/SP_800_53_5_1_1/home?element=ac-11.1)
- [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 (none) reviewed

