Post-Cutoff

“A post on how we’ve been securing our frontier model training environment.”

Greg Brockman @gdbX

Archived text

A post on how we’ve been securing our frontier model training environment.

We’ve been building tools around our frontier cyber models, which have secured us far beyond what we could have unassisted and should generalize as key to how defenders secure themselves going forward.

Quoting @OpenAI: Over the past several months, we have substantially hardened the security of our research training environment. We’ve removed live internet access for all frontier models during training and built an offline world for them to use instead—a cached version of the web where they can still learn to browse, search, and use applications.

On September 20, after a model exploited a DNS misconfiguration to find a way outside of this offline world, we paused frontier training to strengthen containment further. We assembled teams of agents, powered by our most cyber-capable models, and tasked them with finding weaknesses in our research environments.

While they found no route to the internet they could easily exploit while concealing their activity from our monitors, they did find zero-day vulnerabilities, virtual machine escapes, and hardware side-channels for communication between agents. We used their discoveries to further strengthen our defenses and contribute fixes to open-source software.

After strengthening our containment architecture, we resumed our frontier RL training and inference on October 1. We’ve reserved substantial compute for continuous red-teaming, and made high-compute red-teaming part of the safety cases we use to decide whether frontier training and evaluation can proceed securely.

https://openai.com/index/securing-our-frontier-model-training-environment/

Source: x.com/gdb/status/2113724268773023917Archived 2026-10-24 via fxtwitter (unofficial).Counts: 55,310 views, 807 likes, 38 reposts, 112 replies (at fetch time)

Cited in

  1. Policy & safety 115 days after the cutoff

    OpenAI removes live internet access from all frontier-model training, says agent red teams found VM escapes and hardware side channels, and discloses it quietly resumed training on Oct 1