Estimating worst case frontier risks of open weight LLMs
OpenAI just published research on the worst-case risks of open-weight LLMs. Here's what they found when they deliberately tried to break them.

Why it matters
OpenAI's new safety research on open-weight model risks (biology, cybersecurity) is a critical data point in the ongoing debate over open vs. closed model release strategies—directly informing how the industry should think about responsible AI deployment.
The key facts
6 to knowStudy focuses on malicious fine-tuning (MFT) attacks on open-weight LLMs
Two high-risk domains tested: biology and cybersecurity
Research examines worst-case frontier risks of releasing gpt-oss
Published by OpenAI research team
Date: August 5, 2025
Contributes to open vs. closed model governance debate
Go to the source
OpenAI Blogopenai.com
Publisher excerpt: In this paper, we study the worst-case frontier risks of releasing gpt-oss. We introduce malicious fine-tuning (MFT), where we attempt to elicit maximum capabilities by fine-tuning gpt-oss to be as capable as possible in two domains: biology and cybersecurity.
