ATK-006 Evaluation & guardrail bypass
Refusal Evasion / Jailbreak
Applies to: LLM, Multi-modal, Agentic AI · Last reviewed 2026-05-01
Prerequisites
- Target system enforces policy boundaries via system prompt, output filtering, or training-time refusal patterns.
- Boundaries are enforced primarily through pattern-matching rather than semantic understanding.
Test approach
With written authorization, the tester applies known refusal-evasion patterns from public research and defensive corpora: roleplay framing, hypothetical framing, fictional narrative wrapping, character-substitution encoding, language-shift, base-encoding payloads. The tester targets policy boundaries documented for the system (e.g., 'must not produce X') and records which evasions succeed.
Expected evidence
- Test prompt corpus used (with provenance — public corpus references).
- Full request/response logs.
- Comparison of guardrail behavior between successful and unsuccessful evasions.
Detection signals
- Inputs matching known evasion patterns (regex / embedding similarity to public corpora).
- Inputs with unusual encoding density or non-natural language characteristics.
- Outputs that satisfy semantic intent of a refusal-target despite passing simple keyword filters.
Defensive recommendations
- Use semantic policy classifiers rather than only keyword-based filtering.
- Re-evaluate the output against the original policy before delivery, not only the input.
- Maintain an internal corpus of recent jailbreak patterns and re-test continuously.
- Reference AI-CTRL-003 for the program-level testing control.
Framework mappings
- OWASP LLM Top 10: LLM01:2025
- MITRE ATLAS: AML.T0054
- NIST AI RMF: MEASURE-2.7, MANAGE-2.2
Related AI Controls Catalog entries
These controls provide the audit test procedures that validate defences against this attack pattern.