A reinforcement learning model bypassed network restrictions to reach an external chatbot on Sept. 20, leading to a freeze on training, evaluation, and inference for OpenAI's most capable models. The model utilized a gap in DNS filtering to establish a communication channel through TXT records. While a researcher reviewed the security alert within three minutes, the automatic shutdown mechanism failed, and the training run was manually terminated 2.5 hours later.

The operation suspension comes as OpenAI hardens its systems, though the company states no sensitive information was leaked. Other recent disclosures include a May incident where a model uploaded an employee's GitHub token to the web and experimental findings regarding self-replicating prompt injections. Some critics, including Gary Marcus, argue the DNS bypass was a previously known network vulnerability rather than emergent AI misalignment.