no code implementations • 29 Mar 2025 • Chengkun Wei, Weixian Li, Chen Gong, Wenzhi Chen
In this paper, we propose Dynamic Clipping DP-SGD (DC-SGD), a framework that leverages differentially private histograms to estimate gradient norm distributions and dynamically adjust the clipping threshold C. Our framework includes two novel mechanisms: DC-SGD-P and DC-SGD-E. DC-SGD-P adjusts the clipping threshold based on a percentile of gradient norms, while DC-SGD-E minimizes the expected squared error of gradients to optimize C. These dynamic adjustments significantly reduce the burden of hyperparameter tuning C. The extensive experiments on various deep learning tasks, including image classification and natural language processing, show that our proposed dynamic algorithms achieve up to 9 times acceleration on hyperparameter tuning than DP-SGD.
1 code implementation • 11 Mar 2025 • Wenlong Meng, Fan Zhang, Wendao Yao, Zhenyuan Guo, Yuwei Li, Chengkun Wei, Wenzhi Chen
Our experiments show that DIA achieves state-of-the-art attack success rates on recent LLMs, including Llama-3. 1 and GPT-4o.
1 code implementation • 18 Feb 2025 • Wenlong Meng, Zhenyuan Guo, Lenan Wu, Chen Gong, Wenyan Liu, Weixian Li, Chengkun Wei, Wenzhi Chen
In the second stage, we design a new criterion to score each PII candidate and rank them.
1 code implementation • 17 Feb 2025 • Zhenyuan Guo, Yi Shi, Wenlong Meng, Chen Gong, Chengkun Wei, Wenzhi Chen
Specifically, we propose PhiMM, a privacy attack approach that trains a phishing model capable of stealing privacy using a crafted privacy phishing instruction dataset.
1 code implementation • 9 May 2024 • Zhe Ma, Qingming Li, Xuhong Zhang, Tianyu Du, Ruixiao Lin, Zonghui Wang, Shouling Ji, Wenzhi Chen
The past few years have witnessed substantial advances in image generation powered by diffusion models.
1 code implementation • 11 Nov 2023 • Peiyu Liu, Junming Liu, Lirong Fu, Kangjie Lu, Yifan Xia, Xuhong Zhang, Wenzhi Chen, Haiqin Weng, Shouling Ji, Wenhai Wang
Prior works show that ChatGPT has the capabilities of processing foundational code analysis tasks, such as abstract syntax tree generation, which indicates the potential of using ChatGPT to comprehend code syntax and static behaviors.
1 code implementation • 26 Aug 2023 • Chengkun Wei, Wenlong Meng, Zhikun Zhang, Min Chen, Minghu Zhao, Wenjing Fang, Lei Wang, Zihui Zhang, Wenzhi Chen
Instead of directly inverting the triggers, LMSanitator aims to invert the predefined attack vectors (pretrained models' output when the input is embedded with triggers) of the task-agnostic backdoors, which achieves much better convergence performance and backdoor detection accuracy.
1 code implementation • 10 May 2023 • Chengkun Wei, Minghu Zhao, Zhikun Zhang, Min Chen, Wenlong Meng, Bo Liu, Yuan Fan, Wenzhi Chen
We also explore some improvements that can maintain model utility and defend against MIAs more effectively.
no code implementations • 30 Mar 2023 • Chuer Yu, Xuhong Zhang, Yuxuan Duan, Senbo Yan, Zonghui Wang, Yang Xiang, Shouling Ji, Wenzhi Chen
We then visualize the identity loss between the test and the reference image from the image differences of the aligned pairs, and design a custom metric to quantify the identity loss.
no code implementations • 23 Mar 2023 • Yuxuan Duan, Xuhong Zhang, Chuer Yu, Zonghui Wang, Shouling Ji, Wenzhi Chen
We reflect this nature with the confusion of a face identification model and measure the confusion with the maximum value of the output probability distribution.
no code implementations • 3 Oct 2021 • Jiaqi Yang, Xuequan Lu, Wenzhi Chen
In this paper, we focus on a fundamental and practical research problem: judging whether a point cloud is plagiarized or copied to another point cloud in the presence of several manipulations (e. g., similarity transformation, smoothing).