Adaptive Diffusion Freezing: Privacy-preserving Diffusion Models Against Membership Inference Attacks

2026-09-08

AI Summary

本文提出一种名为自适应扩散冻结(ADF)的新框架，通过控制不同数据子集在扩散时间步中的参与度来抵御成员推理攻击，同时平衡隐私、效用和效率。

Abstract

Diffusion models have achieved remarkable success in generative tasks across various areas, however their training process raises significant privacy concerns, particularly under membership inference attacks (MIAs). Prior studies on privacy-preserving of diffusion models fail to balance privacy, utility, and efficiency. To address this gap, we propose a novel framework of privacy-preserving diffusion models, Adaptive Diffusion Freezing (ADF), which can defend against MIAs with better trade-off. By leveraging cross-timestep adaptive freezing training, ADF explicitly control the participation of different data subsets across diffusion timesteps via a mask matrix, which reduces the over-memorization and leads to more uniform model behaviors between member and nonmember samples. To construct a freezing mask matrix that effectively reduce membership leakage without unnecessarily harming generation quality, we introduce a pretraining-based risk-aware freezing policy to estimate MIA risk based on memorization tendency, and suppress the contribution of the subset-timestep pairs with higher risk. Evaluations on multiple datasets demonstrate that ADF provides effective defense performance as well as state-of-the-art privacy-utility-efficiency trade-off performance compared to various baselines.

Problem

• Diffusion Models
• Privacy-preserving
• Membership Inference Attacks
• Utility
• Efficiency

Innovation

• Adaptive Diffusion Freezing
• membership inference attacks
• cross-timestep adaptive freezing training
• risk-aware freezing policy