Control 1.21: Adversarial Input Logging
Control ID: 1.21 Pillar: Security Regulatory Reference: FFIEC CAT 2025, GLBA 501(b), FINRA 4511, OCC 2011-12 Last UI Verified: January 2026 Governance Levels: Baseline / Recommended / Regulated Last Verified: 2026-02-03
Objective
Implement detection and logging capabilities for adversarial inputs targeting AI agents, including prompt injection attacks, jailbreaking attempts, and encoding-based evasion techniques to provide early warning of manipulation attempts and support incident response.
Why This Matters for FSI
- FFIEC CAT 2025: Provides AI-specific threat detection for cybersecurity assessment
- GLBA 501(b): Administrative safeguards through security event detection and logging
- FINRA 4511: Preserves evidence of attack attempts in books and records
- OCC 2011-12: Addresses manipulation attempts on AI models for model risk management
Control Description
This control establishes adversarial detection through:
- Pattern Detection - Identify known adversarial patterns (prompt injection, jailbreaking, role manipulation)
- Encoding Analysis - Detect obfuscated inputs (Base64, Unicode lookalikes, zero-width characters)
- Behavioral Logging - Log suspicious interaction patterns for investigation
- Real-Time Alerting - Alert SOC on high-confidence attack attempts
- Forensic Preservation - Preserve attack evidence for analysis and regulatory response
- Zone-Based Response - Configure logging, alerting, or blocking based on zone risk
Key Configuration Points
- Enable Copilot interaction logging via Purview Audit (Control 1.7)
- Deploy Defender for Cloud Apps AI monitoring policies
- Configure KQL detection queries for adversarial patterns ("ignore previous", "DAN mode", "system prompt")
- Create Sentinel analytics rules with 5-minute detection windows
- Configure Base64 and Unicode obfuscation detection
- Set zone-specific responses: Zone 1 log-only, Zone 2 alert, Zone 3 block
- Preserve attack evidence per retention schedule (6+ years)
Zone-Specific Requirements
| Zone | Requirement | Rationale |
|---|---|---|
| Zone 1 (Personal) | Logging only; weekly review; no blocking | Low risk, avoid disruption |
| Zone 2 (Team) | Alert on high-confidence attacks; optional soft blocking; weekly review | Balanced approach for shared agents |
| Zone 3 (Enterprise) | Full detection including encoding; automatic blocking; real-time SOC alerts; quarterly red team | Maximum protection for customer-facing agents |
Roles & Responsibilities
| Role | Responsibility |
|---|---|
| Entra Security Admin | Configure detection rules, manage Sentinel integration |
| Security Operations | Respond to alerts, investigate detected attacks |
| AI Governance Lead | Policy decisions on blocking vs. logging |
| Compliance Officer | Evidence retention requirements, regulatory reporting |
Related Controls
| Control | Relationship |
|---|---|
| 1.7 - Audit Logging | Provides underlying audit infrastructure |
| 1.8 - Runtime Protection | Complementary threat detection |
| 1.24 - Defender for AI Services | GA threat protection for AI workloads — detects adversarial prompt attacks, credential theft, and data exfiltration targeting Azure OpenAI and other AI services |
| 3.4 - Incident Reporting | Incident response for detected attacks |
| 3.9 - Sentinel Integration | Advanced analytics and correlation |
Implementation Playbooks
Step-by-Step Implementation
This control has detailed playbooks for implementation, automation, testing, and troubleshooting:
- Portal Walkthrough — Step-by-step portal configuration
- PowerShell Setup — Automation scripts
- Verification & Testing — Test cases and evidence collection
- Troubleshooting — Common issues and resolutions
Verification Criteria
Confirm control effectiveness by verifying:
- Test adversarial prompt ("ignore previous instructions") is logged in audit
- Sentinel rule triggers alert/incident on pattern match
- Base64 encoded malicious input is detected by encoding analysis
- Zone 3 blocking helps prevent execution of detected attacks
- Detection report generates with summary statistics
Additional Resources
- Microsoft Learn: Defender for Cloud Apps AI Agent Inventory
- Microsoft Learn: Sentinel Analytics Rules
- Microsoft Learn: Purview Audit Log Search
- OWASP: Top 10 for LLM Applications
Updated: January 2026 | Version: v1.2 | UI Verification Status: Current