Feyospace-v1: a seven-person team trains open-weight frontier cyber agents
feyospace
A data-centric post-training framework for cybersecurity agents built from five training systems plus a resettable-environment data engine, yielding 164,269 verified trajectories for long-context SFT. The released checkpoints improve over their base models by 23.76% on CyberGym and 10.49% on pooled CTF suites; Feyospace-s1 reached 63.24% verified success on the CyberGym leaderboard as of Sep 1, 2026.
Why it matters
The authors present it as the first end-to-end demonstration that a small independent team can train open-weight models with leading agentic cyber capability — a notable entry in offensive-capability open weights.
Importance: 3/5
Small team reaches leading open-weight agentic cyber capability; notable offensive-capability open weights