New research reveals a critical vulnerability in advanced reasoning AI models, where logically inconsistent prompts can force them into 'overthinking,' leading to denial-of-service attacks. This 'Evolutionary Prompt Attack' significantly increases resource consumption and poses a serious threat to commercial LLM providers like OpenAI, Google, and DeepSeek.

DeepSeek's new study explores the effectiveness of learned stopping in reasoning models, finding that it can improve performance in certain tasks. The study introduces LearnStop, a hidden-state-free checkpoint stopper, and evaluates its performance across 18 task-model settings. The results show that learned stopping can be useful in tasks where many questions become correct before full budget but do not exhibit a single reliable scalar stopping signal.