Sybil-based Virtual Data Poisoning Attacks in Federated Learning

Changxun Zhu; Qilong Wu; Lingjuan Lyu; Shibei Xue

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arXiv · 2505.09983

Sybil-based Virtual Data Poisoning Attacks in Federated Learning

Changxun Zhu·Qilong Wu·Lingjuan Lyu·Shibei Xue

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Abstract

Federated learning is vulnerable to poisoning attacks by malicious adversaries. Existing methods often involve high costs to achieve effective attacks. To address this challenge, we propose a sybil-based virtual data poisoning attack, where a malicious client generates sybil nodes to amplify the poisoning model's impact. To reduce neural network computational complexity, we develop a virtual data generation method based on gradient matching. We also design three schemes for target model acquisition, applicable to online local, online global, and offline scenarios. In simulation, our method outperforms other attack algorithms since our method can obtain a global target model under non-independent uniformly distributed data.

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Changxun Zhu, Qilong Wu, Lingjuan Lyu, Shibei Xue. 2025-05-15. Sybil-based Virtual Data Poisoning Attacks in Federated Learning. https://arxiv.org/abs/2505.09983

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