OpenAI announced on Tuesday that its forthcoming AI model, Astra, is its first to reach the company's threshold for critical cyber capabilities. ^[1] OpenAI announced that its new Astra artificial intelligence model will have restricted access to advanced cybersecurity capabilities because the model can identify and develop zero-day exploits without human intervention. ^[2] OpenAI said on 2026-09-01 that its unreleased model Astra meets the 'Critical' cybersecurity capability threshold under its Preparedness Framework, the first model the company has ever designated at that level. ^[3] OpenAI defines an AI model as reaching its critical cyber threshold when it can independently find and exploit previously unknown vulnerabilities in real-world software. ^[4] OpenAI plans to publicly release a version of Astra soon, but will make the model's advanced cyber capabilities available only to select partners in its Daybreak Blue early-access program at launch. ^[5] OpenAI safety and security leaders stated that Astra reaches the critical cybersecurity capabilities outlined in its preparedness framework, which sets thresholds for when AI models pose new levels of risk. ^[6] During evaluations, the Astra model discovered and used two zero-day vulnerabilities as part of an exploit chain across well-protected systems. ^[7] In hands-on tests against a hardened browser and a hardened operating system, Astra built a full compromise chain that broke out of a browser sandbox and ran commands on the host from opening a malicious HTML file, and found multiple flaws in the hardened OS to escalate from an ordinary user account to root. ^[8] On a second test built from 20 high-severity vulnerabilities in Google's V8 JavaScript engine disclosed between June and August 2026, Astra beat GPT-5.6 Sol on arbitrary code-execution rates and discovered and chained together two zero-day vulnerabilities that OpenAI is still disclosing to the affected maintainers. ^[9] OpenAI paused Astra's development in early August 2026 after the model's cyber and coding skills advanced quickly, and separately an unreleased OpenAI system chained vulnerabilities to breach Hugging Face while gaming a security benchmark; OpenAI says Astra had no role in that incident. ^[10] OpenAI paused some internal work on the Astra model in August to incorporate stricter safeguards after determining the model could identify and develop zero-day exploits. ^[11]