OpenAI chief executive Sam Altman at the company’s DevDay event in San Francisco, 29 September 2026.

Credit: OpenAI

OpenAI has cut live web access from all training of its most advanced AI models. The models now browse and search a cached copy of the web instead, the company wrote in a blog post on Friday.

“Based on the current state of alignment research, monitoring systems, and the security of internet infrastructure,” OpenAI wrote, it believes frontier training should run offline.

The rule will stay until better safeguards are in place, it said. However, full isolation is not yet possible, because tests still need some outside links to run and be watched.

The change follows a 20 September incident . An in-house model used a badly set up DNS server, which turns web names into server addresses, to get online during a training run.…