garak is NVIDIA's open-source vulnerability scanner for large language models and related interfaces. It runs probe suites against model generators and uses detectors to identify behaviors such as prompt injection, data leakage, unsafe generation, hallucination, and known attack-pattern responses. Its plugin architecture and machine-readable results make it useful for exploratory testing and regression baselines across supported targets. Coverage depends on selected probes, detectors, configuration, and stochastic model behavior; a finding is a lead for investigation, not by itself proof of exploitability or business impact.
Detailed assessment
Description
garak is NVIDIA's open-source vulnerability scanner for large language models and related interfaces. It runs probe suites against model generators and uses detectors to identify behaviors such as prompt injection, data leakage, unsafe generation, hallucination, and known attack-pattern responses. Its plugin architecture and machine-readable results make it useful for exploratory testing and regression baselines across supported targets. Coverage depends on selected probes, detectors, configuration, and stochastic model behavior; a finding is a lead for investigation, not by itself proof of exploitability or business impact. Researchers can select generator adapters, probe families, detectors, and reporting options to test local models or supported services, then preserve outputs for triage or comparison after a change. It complements orchestration frameworks such as PyRIT and application-level suites such as Promptfoo by emphasizing broad probe coverage. The project is free and versioned on GitHub; pin releases, document model parameters, and repeat runs because model responses vary. Testing may consume paid APIs or produce harmful content, so use authorized endpoints, isolated output handling, rate limits, and human-reviewed success criteria.
Strengths
- Offers a broad, extensible catalog of probes, model interfaces, and response detectors.
- Supports repeatable command-line testing and machine-readable result analysis.
- Makes common LLM attack patterns accessible for baseline and exploratory evaluation.
Limitations
- Detector false positives and negatives require manual review and context-specific success criteria.
- Probe coverage cannot represent every application workflow, guardrail, or downstream consequence.
Best for
- LLM vulnerability exploration
- model safety regression testing
- attack-surface discovery
- research comparisons
Quality dimensions
- Authority 4.5/5
- Originality 5/5
- Maintenance 5/5
- Practical_value 4.7/5
- Transparency 5/5
Offers a broad, extensible catalog of probes, model interfaces, and response detectors; principal limitation: Detector false positives and negatives require manual review and context-specific success criteria.
Audience
- ai security engineers
- model evaluators
- red teams
- researchers
Formats
- open-source software
- command-line tool
- documentation
- plugins
- scan reports
Keywords
- ai-security
- llm-security
- vulnerability-scanning
- adversarial-testing
- prompt-injection
- model-evaluation
- red-team
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