arXiv AI By Kun Zhai, Teng Li, Yunhao Feng, Xingjun Ma

ShadowFPT: Backdooring Federated Prompt Tuning via Shadow Triggers

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ShadowFPT is a targeted backdoor attack on Federated Prompt Tuning (FPT) that exploits the frozen backbone of large vision–language models. The attack pretrains a learnable Shadow Trigger to steer representations toward a target class, then adapts the trigger and local prompt during federated training while only uploading prompt updates. This method raises the attack success rate from 19.81% to 90.36% across various datasets and settings, yet preserves clean accuracy and remains effective for textual, visual, and joint prompt tuning.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv AI.

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