arXiv Machine Learning By Ali Al-Lawati, Elsayed Eshra, Dongwon Lee, Suhang Wang

Diffusion Language Models for Perplexity-Aware Black-Box Attacks

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The paper introduces Diffusion Language Models for Perplexity-Aware Black-Box Attacks, replacing the random mapping used in continuous-space attacks with a learned generative distribution over language. This approach preserves the Gaussian latent formulation while producing more natural prompts, leading to dramatic reductions in character-level perplexity—from thousands to single digits—in both sampling-based (RareTrap) and optimization-based (ThinkTrap) settings. The study also shows that risk estimates can vary by an order of magnitude depending on the mapping used.

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