Booz Allen runs 18 models as autonomous attackers and says one completed a full intrusion unaided
Booz Allen's Cyber Weapon Index ran 18 leading US and Chinese models against production-grade enterprise networks, each controlling a real attacker machine with no curated tool menu, and reports that one model — Anthropic's Claude Mythos — executed the full cyber kill chain autonomously, four more reached full domain access and control, four managed lateral movement, two progressed through credential access and all but one penetrated the network, with no substantial separation between the US and Chinese models. The accompanying report scores Claude Mythos at 80, Grok-4.5 at 49, GPT-5.6 Sol at 46 and Muse Spark 1.1 at 38, says a lower-ranked model paired with an attack harness rivalled the top scorer, and states that “the model is no longer the unit of risk. The system is.”