GPT-5.6 Sol’s ExploitGym score shows a specific cyber gain, not autonomous reliability
OpenAI says GPT-5.6 Sol reached a 24.9% ExploitGym pass rate under a two-hour cap, up from GPT-5.5’s 15.1%. The benchmark measures a bounded step from a known vulnerability to an exploit; a separate assessment performed with OpenAI finds continued limits on hardened targets and long operations.
- OpenAI says GPT-5.6 Sol scored 24.9% on ExploitGym under a two-hour cap, versus 15.1% for GPT-5.5.
- ExploitGym asks an agent to turn an already triggering input for a real vulnerability into a working exploit; it does not test every stage of an intrusion.
- A separate assessment performed with OpenAI found Sol only slightly stronger than GPT-5.5 overall, with continuing weaknesses on hardened systems and long, time-sensitive work.
OpenAI, the AI developer releasing GPT-5.6 Sol as the flagship tier of its newly available model family, says Sol made a large gain over its predecessor on ExploitGym. The model reached a 24.9% pass rate under a two-hour cap, against GPT-5.5’s 15.1%, according to the company’s release.
That is a consequential result on a difficult exploitation task. It is not, by itself, evidence that a deployed model can reliably conduct an autonomous cyber operation. The benchmark starts after a vulnerability has been triggered; a separate evaluation says Sol still has clear limits against hardened targets and in the orchestration and operationalization of attacks.

ExploitGym pass rates under a two-hour cap, company-reported. Source: OpenAI.
What the ExploitGym result measures
ExploitGym is a containerized benchmark introduced by Zhun Wang and 15 co-authors. It contains 898 instances drawn from real-world vulnerabilities in userspace programs, Google’s V8 JavaScript engine and the Linux kernel. Given an input that triggers a flaw, an agent must progressively extend it into a working exploit, as the paper explains.
That scope is narrower than finding an unknown flaw, choosing a target, sustaining an operation or avoiding detection. It is still a meaningful dual-use capability: the paper says exploitation can help defenders validate and fix flaws while also lowering the barrier to offensive work.
OpenAI reports that Sol reached 33.7% on ExploitGym with six hours. It also reports a 73.5% ExploitBench score, versus 47.9% for GPT-5.5 at a comparable output-token budget, and a 71.2% SEC-Bench Pro score, versus 45.8% for GPT-5.5. Those are separate evaluations with different task definitions, so they should not be combined into a single measure of cyber capability.
The ExploitGym paper provides an important competitive baseline as well. In its own evaluation, the strongest listed configurations—Claude Mythos Preview and GPT-5.5—generated working exploits for 157 and 120 instances, respectively. Its conclusion was not that exploitation had become routine: frontier models succeeded on a non-trivial fraction of tasks, including some with commonly used defenses enabled, but the task remained challenging.