Open source AI refers to AI systems released so people can use, study, modify, and share them, with access to the preferred form for making changes, such as source code, weights, or training artifacts. That is broader than a chatbot or API that only exposes outputs. The key security value is verifiability: independent researchers and defenders can inspect how the system behaves, test for weaknesses, and confirm safety or privacy claims.
In cyber security, open source AI can help defenders reproduce results, audit model behavior, and detect unsafe defaults, hidden prompts, or data leakage risks. It can also help attackers analyze models for misuse opportunities, fine-tune them for spam, phishing, or malware assistance, and adapt them without vendor controls. Because of that dual use, open source AI is often discussed alongside governance, release thresholds, and model monitoring. Openness improves transparency, but it does not automatically make a model safe; security depends on how it is built, tested, and used.