Backdoor Attacks and Defenses in Federated Learning: State-of-the-Art, Taxonomy, and Future Directions
Abstract
The federated learning framework is designed for massively distributed training of deep learning models among thousands of participants without compromising the privacy of their training datasets. The training dataset across participants usually has heterogeneous data distributions. Besides, the central server aggregates the updates provided by different parties, but has no visibility into how such updates are created. The inherent characteristics of federated learning may incur a severe security concern. The malicious participants can upload poisoned updates to introduce backdoored functionality into the global model, in which the backdoored global model will misclassify all the malicious images (i.e., attached with the backdoor trigger) into a false label but will behave normally in the absence of the backdoor trigger. In this work, we present a comprehensive review of the state-of-the-art backdoor attacks and defenses in federated learning. We classify the existing backdoor attacks into two categories: data poisoning attacks and model poisoning attacks, and divide the defenses into anomaly updates detection, robust federated training, and backdoored model restoration. We give a detailed comparison of both attacks and defenses through experiments. Lastly, we pinpoint a variety of potential future directions of both backdoor attacks and defenses in the framework of federated learning.
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In some existing surveys, theoretical working mechanisms of backdoor attacks and defenses for WFL were reviewed, but limitations of existing methodologies were not systematically analyzed.
“In [52] and [53], the theoretical working mechanisms of backdoor attacks and defenses for WFL were reviewed. However, the limitations of the existing methodologies were not systematically analyzed.”
From Data and model poisoning backdoor attacks on wireless federated learning, and the defense mechanisms: A comprehensive survey (2024) · cites this paper as [52]
The low-dimensional embeddings of the uploaded model updates still contain the crucial features that capture the essential variability in data instances.
“This considers the fact that the low-dimensional embeddings of the uploaded model updates still contain the crucial features that capture the essential variability in data instances [52].”
From Data and model poisoning backdoor attacks on wireless federated learning, and the defense mechanisms: A comprehensive survey (2024) · cites this paper as [52]
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“This considers the fact that the low-dimensional embeddings of the uploaded model updates still contain the crucial features that capture the essential variability in data instances [52].”
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- Authors
- Gong, X., Chen, Y., Wang, Q., & Kong, W.
- Affiliations
- Wuhan University (CN)
- Zhejiang University (CN)
- Venue
- IEEE Wireless Communications
- Published
- 2023-04
- Volume
- 30
- Issue
- 2
- Pages
- 114-121
- ISSN
- 1536-1284 (ISSN-L)
- 1558-0687
- OpenAlex
- W4285206772
- Cited by
- 114
- References
- 15
- Citations by year
- 2026: 22 · 2025: 41 · 2024: 29 · 2023: 21 · 2022: 1
- FWCI
- 7.57
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- Locations
- IEEE Wireless Communications (publishedVersion)
- Funders
- NSFC (U20B2049,U21B2018)
- National Natural Science Foundation of China (61972296)
- Topics
- Physical Sciences › Computer Science › Artificial Intelligence › Adversarial Robustness in Machine Learning
- Physical Sciences › Computer Science › Artificial Intelligence › Privacy-Preserving Technologies in Data
- Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Digital Media Forensic Detection
- Keywords
- backdoor attacks, federated learning, backdoor defense, data poisoning, model poisoning, malicious participants, backdoor triggers, privacy-preserving machine learning, attack taxonomy
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