A short audio clip prepended to live speech can steer what an AI writes down.
AspireAI community · arXiv (GhostPrefix)
*A short audio clip prepended to live speech can steer what an AI writes down.*
GhostPrefix is a universal adversarial prefix for automatic speech recognition: one reusable segment, no knowledge of the coming utterance, no timing alignment needed. Across 13 open ASR models in digital tests it steered transcripts 97.6 percent of the time and forced a chosen transcript 93.4 percent of the time, and over the air it still managed 91.5 and 89.5 percent.
The attacks carried straight into downstream tools: voice assistants and AI note-takers were pushed into systematic misreadings of what was said.
The honest limit: the evaluation covers open ASR models, not the hosted commercial ones most products actually call.
https://arxiv.org/abs/2610.42026
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