# Chameleon: Adapting to Peer Images for Planting Durable Backdoors in Federated Learning

arXiv: https://arxiv.org/abs/2304.12961 · HTML: https://mlsanity.com/paper/2304.12961/

## Key facts

- Cited by 21 papers in the map (data through 14 Oct 2026).
- Builds on 29 of its 47 references that are in the map.
- First posted on arXiv 25 Apr 2023.

## Builds on (most cited first, 29 of 29)

- [A Simple Framework for Contrastive Learning of Visual Representations](https://mlsanity.com/paper/2002.05709/) (2020)
- [Communication-Efficient Learning of Deep Networks from Decentralized Data](https://mlsanity.com/paper/1602.05629/) (2016)
- [Momentum Contrast for Unsupervised Visual Representation Learning](https://mlsanity.com/paper/1911.05722/) (2019)
- [Overcoming catastrophic forgetting in neural networks](https://mlsanity.com/paper/1612.00796/) (2016)
- [Federated Optimization in Heterogeneous Networks](https://mlsanity.com/paper/1812.06127/) (2018)
- [Supervised Contrastive Learning](https://mlsanity.com/paper/2004.11362/) (2020)
- [Targeted Backdoor Attacks on Deep Learning Systems Using Data Poisoning](https://mlsanity.com/paper/1712.05526/) (2017)
- [Measuring the Effects of Non-Identical Data Distribution for Federated Visual Classification](https://mlsanity.com/paper/1909.06335/) (2019)
- [How To Backdoor Federated Learning](https://mlsanity.com/paper/1807.00459/) (2018)
- [Inverting Gradients -- How easy is it to break privacy in federated learning?](https://mlsanity.com/paper/2003.14053/) (2020)
- [Byzantine-Robust Distributed Learning: Towards Optimal Statistical Rates](https://mlsanity.com/paper/1803.01498/) (2018)
- [Poison Frogs! Targeted Clean-Label Poisoning Attacks on Neural Networks](https://mlsanity.com/paper/1804.00792/) (2018)
- [Local Model Poisoning Attacks to Byzantine-Robust Federated Learning](https://mlsanity.com/paper/1911.11815/) (2019)
- [Hidden Trigger Backdoor Attacks](https://mlsanity.com/paper/1910.00033/) (2019)
- [Analyzing Federated Learning through an Adversarial Lens](https://mlsanity.com/paper/1811.12470/) (2018)
- [Reflection Backdoor: A Natural Backdoor Attack on Deep Neural Networks](https://mlsanity.com/paper/2007.02343/) (2020)
- [The Hidden Vulnerability of Distributed Learning in Byzantium](https://mlsanity.com/paper/1802.07927/) (2018)
- [Attack of the Tails: Yes, You Really Can Backdoor Federated Learning](https://mlsanity.com/paper/2007.05084/) (2020)
- [Can You Really Backdoor Federated Learning?](https://mlsanity.com/paper/1911.07963/) (2019)
- [Privacy and Robustness in Federated Learning: Attacks and Defenses](https://mlsanity.com/paper/2012.06337/) (2020)
- [Demon in the Variant: Statistical Analysis of DNNs for Robust Backdoor Contamination Detection](https://mlsanity.com/paper/1908.00686/) (2019)
- [Back to the Drawing Board: A Critical Evaluation of Poisoning Attacks on Production Federated Learning](https://mlsanity.com/paper/2108.10241/) (2021)
- [Neurotoxin: Durable Backdoors in Federated Learning](https://mlsanity.com/paper/2206.10341/) (2022)
- [CRFL: Certifiably Robust Federated Learning against Backdoor Attacks](https://mlsanity.com/paper/2106.08283/) (2021)
- [DeepSight: Mitigating Backdoor Attacks in Federated Learning Through Deep Model Inspection](https://mlsanity.com/paper/2201.00763/) (2022)
- [Local and Central Differential Privacy for Robustness and Privacy in Federated Learning](https://mlsanity.com/paper/2009.03561/) (2020)
- [BaFFLe: Backdoor detection via Feedback-based Federated Learning](https://mlsanity.com/paper/2011.02167/) (2020)
- [Shielding Collaborative Learning: Mitigating Poisoning Attacks through Client-Side Detection](https://mlsanity.com/paper/1910.13111/) (2019)
- [Thinking Two Moves Ahead: Anticipating Other Users Improves Backdoor Attacks in Federated Learning](https://mlsanity.com/paper/2210.09305/) (2022)

## Built on by (most cited first, 21 of 21)

- [Federated Learning for Generalization, Robustness, Fairness: A Survey and Benchmark](https://mlsanity.com/paper/2311.06750/) (2023)
- [FLTracer: Accurate Poisoning Attack Provenance in Federated Learning](https://mlsanity.com/paper/2310.13424/) (2023)
- [MARS: A Malignity-Aware Backdoor Defense in Federated Learning](https://mlsanity.com/paper/2509.20383/) (2025)
- [FedAA: A Reinforcement Learning Perspective on Adaptive Aggregation for Fair and Robust Federated Learning](https://mlsanity.com/paper/2402.05541/) (2024)
- [SDBA: A Stealthy and Long-Lasting Durable Backdoor Attack in Federated Learning](https://mlsanity.com/paper/2409.14805/) (2024)
- [On the Security and Privacy of Federated Learning: A Survey with Attacks, Defenses, Frameworks, Applications, and Future Directions](https://mlsanity.com/paper/2508.13730/) (2025)
- [Towards Understanding Adversarial Transferability in Federated Learning](https://mlsanity.com/paper/2310.00616/) (2023)
- [Attack On Prompt: Backdoor Attack in Prompt-Based Continual Learning](https://mlsanity.com/paper/2406.19753/) (2024)
- [Non-Cooperative Backdoor Attacks in Federated Learning: A New Threat Landscape](https://mlsanity.com/paper/2407.07917/) (2024)
- [Mind the Cost of Scaffold! Benign Clients May Even Become Accomplices of Backdoor Attack](https://mlsanity.com/paper/2411.16167/) (2024)
- [DBA-DFL: Towards Distributed Backdoor Attacks with Network Detection in Decentralized Federated Learning](https://mlsanity.com/paper/2501.15005/) (2025)
- [DROP: Poison Dilution via Knowledge Distillation for Federated Learning](https://mlsanity.com/paper/2502.07011/) (2025)
- [Defending the Edge: Representative-Attention Defense against Backdoor Attacks in Federated Learning](https://mlsanity.com/paper/2505.10297/) (2025)
- [BackFed: An Efficient & Standardized Benchmark Suite for Backdoor Attacks in Federated Learning](https://mlsanity.com/paper/2507.04903/) (2025)
- [FTA: Stealthy and Adaptive Backdoor Attack with Flexible Triggers on Federated Learning](https://mlsanity.com/paper/2309.00127/) (2023)
- [A Whole-Process Certifiably Robust Aggregation Method Against Backdoor Attacks in Federated Learning](https://mlsanity.com/paper/2407.00719/) (2024)
- [TrojanDam: Detection-Free Backdoor Defense in Federated Learning through Proactive Model Robustification utilizing OOD Data](https://mlsanity.com/paper/2504.15674/) (2025)
- [Coward: Collision-based OOD Watermarking for Practical Proactive Federated Backdoor Detection](https://mlsanity.com/paper/2508.02115/) (2025)
- [FLAT: Revealing Hidden Latent-Conditioned Backdoor Failures in Federated Learning](https://mlsanity.com/paper/2508.04064/) (2025)
- [Enhancing the Effectiveness and Durability of Backdoor Attacks in Federated Learning through Maximizing Task Distinction](https://mlsanity.com/paper/2509.18904/) (2025)
- [Mitigating Backdoor Attacks in Federated Learning Using PPA and MiniMax Game Theory](https://mlsanity.com/paper/2603.28652/) (2026)

## Abstract (arXiv)

In a federated learning (FL) system, distributed clients upload their local models to a central server to aggregate into a global model. Malicious clients may plant backdoors into the global model through uploading poisoned local models, causing images with specific patterns to be misclassified into some target labels. Backdoors planted by current attacks are not durable, and vanish quickly once the attackers stop model poisoning. In this paper, we investigate the connection between the durability of FL backdoors and the relationships between benign images and poisoned images (i.e., the images whose labels are flipped to the target label during local training). Specifically, benign images with the original and the target labels of the poisoned images are found to have key effects on backdoor durability. Consequently, we propose a novel attack, Chameleon, which utilizes contrastive learning to further amplify such effects towards a more durable backdoor. Extensive experiments demonstrate that Chameleon significantly extends the backdoor lifespan over baselines by 1.2× ~ 4×, for a wide range of image datasets, backdoor types, and model architectures.
