Open-weight AI model GLM-5.3 cheated its way to correct answers

Irregular evaluated Zhipu AI’s open-weight model GLM-5.3 across 13 offensive cyber scenarios using CyScenarioBench, the company’s framework for measuring an LLM’s ability to plan and execute multistage attacks under realistic constraints. The model refused none of the tasks and completed three scenarios at least once each, carrying attacks through dependent stages to reach objectives in simulated networks. Irregular said this was the strongest result it had recorded for an open-weight model.