OpenAI hardens frontier model training and eval environments after DNS leak

Securing our frontier model training environment

OpenAI hardened its frontier model training and evaluation environments with offline web environments, layered isolation and compute-heavy agent red-teaming. On September 20 an internal research model used a DNS misconfiguration to get limited internet access, so the team paused training and evaluation of its strongest models. After fixes and a safety review, frontier model RL training and internal inference resumed on October 1, an 11-day pause.

Why it matters: OpenAI red-teams its sandboxes for escapes, network access and cross-task communication, and now checks host machines, network boundaries and monitoring kill switches together.