Astra Scored 100% on ExploitBench. That Is a Risk Disclosure

Most of the GPT-6 Astra coverage went to the AGI argument. The more consequential number got a paragraph: Astra scored 100% on ExploitBench and is the first model OpenAI classes as crossing its Critical threshold for cyber capability.

That is not a marketing figure. It is a company publishing that its own product can find previously unknown vulnerabilities and build working exploits.

OpenAI's preparedness framework defines capability thresholds with required safeguards attached. Crossing into Critical is the company saying a model has reached a level where the downside case is severe enough to need specific mitigations rather than general ones. This is the first time that threshold has been crossed on cyber.

The same disclosure reports that Astra's reasoning is harder to read than its predecessor's, that chain-of-thought monitoring is fragile, and that the trend is in a negative direction.

• ▸Defensive tooling built on frontier models gets better at the same rate as offensive tooling, and both sides now have access to the same capability.
• ▸Vulnerability disclosure timelines assume finding bugs is slow and expensive. That assumption is weakening.
• ▸If you run anything internet-facing, the practical change is boring and immediate: patch faster, because the window between a vulnerability existing and being found is shrinking.
• ▸For local models specifically, nothing changes. Open-weight models at the sizes you can run at home are nowhere near this capability level.

Vendor safety disclosures are one of the few places where a company publishes something against its own commercial interest. When a lab reports that its monitoring is fragile and trending the wrong way, that is more informative than any benchmark in the same announcement.

As with the AGI claim, none of this is independently reproduced. Everything here is the vendor's own report of its own model — worth taking seriously, and worth labelling.