An open model is an AI model whose weights, code, training details, or other development outputs are made publicly available for inspection, testing, or reuse. Compared with a closed model, it gives researchers and defenders more visibility into how the system was built and how it behaves.
In cybersecurity, that visibility matters because it supports auditing, reproducibility, and red-teaming. Security teams can evaluate whether the model leaks data, follows unsafe prompts, or amplifies risky behavior. At the same time, open access can lower the barrier for abuse: threat actors may fine-tune the model for phishing, malware assistance, vulnerability discovery, or automated social engineering. For defenders, the key issue is not openness itself, but how responsibly the model is released, monitored, and adapted for cyber tasks.