Plausible but wrong output, such as invented facts, citations, packages or code, causes harm when people or systems act on it without checking.
- Ground answers in retrieved, authoritative sources, and show citations that users can check.
- Validate model output before it drives decisions or automation, and keep a person in the loop for consequential actions.
- Tell users where output may be unreliable, and evaluate accuracy on your own domain.
Guides on this site
Contain LLM misinformation (OWASP LLM07:2026)
Stop plausible but wrong model output from driving decisions and actions: ground answers in sources, verify every citation, separate generation from execution with a claim-check-act pattern, gate consequential actions on a human, and evaluate factuality on your own domain.
Keep generated output out of executable contexts
Choose safe rendering and narrow operations so model text cannot become browser code, database syntax or an unrestricted command.
Build evaluations around prohibited outcomes
Test the application’s actual security boundaries, preserve legitimate tasks and distinguish deterministic enforcement from variable model behavior.
Case study: Moffatt v. Air Canada, a chatbot that misstated the refund policy (2022-2024)
How an airline's website chatbot told a grieving customer they could claim a bereavement fare after travel, what the British Columbia Civil Resolution Tribunal decided in February 2024, and the grounding, testing and correction practices that keep an automated answer consistent with the policy it describes.
Practice
- XSS lab: Render a model’s answer as text instead of active markup · Browser lab
- Gate model and provider changes on a versioned red-team corpus · Local project
- Run model-generated Python in a locked-down container · Local project
References
- LLM09:2025 Misinformation (OWASP, 2025 edition)
- OWASP Top 10 for LLM Applications 2026 (OWASP GenAI Security Project resource page)
List data from the publisher. A guide is listed as the main subject when the weakness or risk is what the guide is about, and as covering it when a dedicated section or worked example addresses it.