arXiv Machine Learning By Kai Li, Hanlin Cai, Zihao Liu, Yichen Li, Jose Alcaraz Calero, Wei Ni, Falko Dressler, \"Ozg\"ur B. Akan

Byzantine-Resilient Federated Large Language Model via Hypergraph Message Passing

Read the original on arXiv Machine Learning →

The paper introduces a Byzantine‑resilient federated large language model (FedLLM) that uses a Hypergraph Message Passing Graph Autoencoder (HMP‑GAE) to prevent semantically corrupted updates from spreading during aggregation. By representing low‑rank model updates as hypergraph nodes and iteratively passing messages, HMP‑GAE jointly maximizes global accuracy and suppresses malicious updates without accessing private data. Experiments on AG News and Yahoo! Answers with Qwen‑2.5 and Llama‑3.2 backbones show significant gains: 1.21% higher accuracy, 44.08% lower semantic entropy, and 13.34% reduced perplexity compared to existing defenses.

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arXiv AI
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FedLSG: LLM-Enhanced Semantic Calibration for Federated Graph Backdoor Defense

arXiv:2607. 19674v1 Announce Type: cross Abstract: Federated Graph Neural Networks (FedGNNs) are highly vulnerable to backdoor poisoning, yet existing defenses typically rely on rule-based approaches that lack semantic understanding, making them vulnerable to stealthy triggers and harmful to benign structures.

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5d ago

FedGraph: Defending Federated Large Language Model Fine-Tuning Against Backdoor Attacks via Graph-Based Aggregation

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By Xi Chen, Chunyi Zhou, Rui Zeng, Xiaogang Xu, Zhe Liu, Shouling Ji
arXiv Machine Learning
Aug 20

FedLNS: Leverage LayerNorm Signature Modeling to Mitigate Adversarial Manipulation in Federated LLMs

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By Kai Li, Jong-Ik Park, Carlee Joe-Wong, Wei Ni, Falko Dressler
arXiv AI
1d ago

S-GAP: Stealthy Graph Attack Primitives for Graph Large Language Models

The paper introduces S‑GAP, a stealthy graph attack primitive that unifies textual and structural perturbations into a single coherent attack intent for Graph Large Language Models (GraphLLMs). By iteratively refining the semantic content of the GAP through a multi‑agent framework, S‑GAP achieves higher attack success rates and produces more relationally plausible perturbations compared to existing methods. Experiments on four datasets and three GraphLLMs demonstrate an average 7.02% improvement in attack success rate, revealing significant vulnerabilities in current GraphLLMs.

By Wenda Li, Tongya Zheng, Shunyu Liu, Hanyang Yuan, Kaixuan Chen, Yu Wang, Yuchen Ying, Haoze Jiang, Huan Li, Gang Chen, Zujie Ren