OpenAI Astra achieves 3.4x exploit success rate vs GPT-5.6 with 45% fewer tokens

imjustnewatai · x · 2026-09-02

OpenAI's upcoming security model Astra shows strong performance in internal testing. On a set of 20 high-severity vulnerabilities, Astra achieved a 39% exploit success rate using 76k output tokens, compared to GPT-5.6's 11.5% using 138k tokens. This represents a 3.4x higher success rate with 45% fewer tokens. Astra also discovered and used two zero-days in an exploit chain. While Fable 5.1's launch sparked comparisons, Astra is not yet public. The real shift is cheaper repetition (more exploit paths per token), with OpenAI countering via runtime supervision.

Related event: OpenAI's Astra Aces ExploitBench with Massive Exploit Gains(4 posts)→

Original post →

More from Models

Models channel →