Search Results for author: Junfeng Guo

Found 28 papers, 6 papers with code

Practical Poisoning Attacks on Neural Networks

no code implementations ECCV 2020 Junfeng Guo, Cong Liu

Importantly, we show that the effectiveness of BlackCard can be intuitively guaranteed by a set of analytical reasoning and observations, through exploiting an essential characteristic of gradient-descent optimization which is pervasively adopted in DNN models.

Data Poisoning

CertDW: Towards Certified Dataset Ownership Verification via Conformal Prediction

no code implementations16 Jun 2025 Ting Qiao, Yiming Li, Jianbin Li, Yingjia Wang, Leyi Qi, Junfeng Guo, Ruili Feng, DaCheng Tao

If the number of PP values smaller than WR exceeds a threshold, the suspicious model is regarded as having been trained on the protected dataset.

CoTGuard: Using Chain-of-Thought Triggering for Copyright Protection in Multi-Agent LLM Systems

no code implementations26 May 2025 Yan Wen, Junfeng Guo, Heng Huang

As large language models (LLMs) evolve into autonomous agents capable of collaborative reasoning and task execution, multi-agent LLM systems have emerged as a powerful paradigm for solving complex problems.

Modality-Balancing Preference Optimization of Large Multimodal Models by Adversarial Negative Mining

no code implementations20 May 2025 Chenxi Liu, Tianyi Xiong, Ruibo Chen, Yihan Wu, Junfeng Guo, Tianyi Zhou, Heng Huang

Meanwhile, Group Relative Policy Optimization (GRPO), a recent method using online-generated data and verified rewards to improve reasoning capabilities, remains largely underexplored in LMM alignment.

Large Language Model

Asymmetric Conflict and Synergy in Post-training for LLM-based Multilingual Machine Translation

no code implementations16 Feb 2025 Tong Zheng, Yan Wen, Huiwen Bao, Junfeng Guo, Heng Huang

The emergence of Large Language Models (LLMs) has advanced the multilingual machine translation (MMT), yet the Curse of Multilinguality (CoM) remains a major challenge.

Machine Translation

Improved Unbiased Watermark for Large Language Models

no code implementations16 Feb 2025 Ruibo Chen, Yihan Wu, Junfeng Guo, Heng Huang

As artificial intelligence surpasses human capabilities in text generation, the necessity to authenticate the origins of AI-generated content has become paramount.

Language Modeling Language Modelling +1

Towards Copyright Protection for Knowledge Bases of Retrieval-augmented Language Models via Reasoning

no code implementations10 Feb 2025 Junfeng Guo, Yiming Li, Ruibo Chen, Yihan Wu, Chenxi Liu, Yanshuo Chen, Heng Huang

Large language models (LLMs) are increasingly integrated into real-world personalized applications through retrieval-augmented generation (RAG) mechanisms to supplement their responses with domain-specific knowledge.

Anomaly Detection RAG +2

SleeperMark: Towards Robust Watermark against Fine-Tuning Text-to-image Diffusion Models

1 code implementation CVPR 2025 Zilan Wang, Junfeng Guo, Jiacheng Zhu, Yiming Li, Heng Huang, Muhao Chen, Zhengzhong Tu

Recent advances in large-scale text-to-image (T2I) diffusion models have enabled a variety of downstream applications, including style customization, subject-driven personalization, and conditional generation.

Backdoor in Seconds: Unlocking Vulnerabilities in Large Pre-trained Models via Model Editing

no code implementations23 Oct 2024 Dongliang Guo, Mengxuan Hu, Zihan Guan, Junfeng Guo, Thomas Hartvigsen, Sheng Li

Through empirical studies on the capability for performing backdoor attack in large pre-trained models ($\textit{e. g.,}$ ViT), we find the following unique challenges of attacking large pre-trained models: 1) the inability to manipulate or even access large training datasets, and 2) the substantial computational resources required for training or fine-tuning these models.

Backdoor Attack Image Captioning +4

De-mark: Watermark Removal in Large Language Models

no code implementations17 Oct 2024 Ruibo Chen, Yihan Wu, Junfeng Guo, Heng Huang

Watermarking techniques offer a promising way to identify machine-generated content via embedding covert information into the contents generated from language models (LMs).

A Watermark for Order-Agnostic Language Models

no code implementations17 Oct 2024 Ruibo Chen, Yihan Wu, Yanshuo Chen, Chenxi Liu, Junfeng Guo, Heng Huang

Correspondingly, we propose a statistical pattern-based detection algorithm that recovers the key sequence during detection and conducts statistical tests based on the count of high-frequency patterns.

Few-Shot Class Incremental Learning with Attention-Aware Self-Adaptive Prompt

1 code implementation14 Mar 2024 Chenxi Liu, Zhenyi Wang, Tianyi Xiong, Ruibo Chen, Yihan Wu, Junfeng Guo, Heng Huang

Few-Shot Class-Incremental Learning (FSCIL) models aim to incrementally learn new classes with scarce samples while preserving knowledge of old ones.

class-incremental learning Few-Shot Class-Incremental Learning +1

Federated Continual Novel Class Learning

no code implementations21 Dec 2023 Lixu Wang, Chenxi Liu, Junfeng Guo, Jiahua Dong, Xiao Wang, Heng Huang, Qi Zhu

In a privacy-focused era, Federated Learning (FL) has emerged as a promising machine learning technique.

Federated Learning Novel Class Discovery +1

Towards Sample-specific Backdoor Attack with Clean Labels via Attribute Trigger

no code implementations3 Dec 2023 Mingyan Zhu, Yiming Li, Junfeng Guo, Tao Wei, Shu-Tao Xia, Zhan Qin

We argue that the intensity constraint of existing SSBAs is mostly because their trigger patterns are `content-irrelevant' and therefore act as `noises' for both humans and DNNs.

Attribute Backdoor Attack

A Resilient and Accessible Distribution-Preserving Watermark for Large Language Models

2 code implementations11 Oct 2023 Yihan Wu, Zhengmian Hu, Junfeng Guo, Hongyang Zhang, Heng Huang

Watermarking techniques offer a promising way to identify machine-generated content via embedding covert information into the contents generated from language models.

Language Modeling Language Modelling

PolicyCleanse: Backdoor Detection and Mitigation for Competitive Reinforcement Learning

no code implementations ICCV 2023 Junfeng Guo, Ang Li, Lixu Wang, Cong Liu

To ensure the security of RL agents against malicious backdoors, in this work, we propose the problem of Backdoor Detection in multi-agent RL systems, with the objective of detecting Trojan agents as well as the corresponding potential trigger actions, and further trying to mitigate their bad impact.

Machine Unlearning reinforcement-learning +2

PolicyCleanse: Backdoor Detection and Mitigation in Reinforcement Learning

no code implementations8 Feb 2022 Junfeng Guo, Ang Li, Cong Liu

To ensure the security of RL agents against malicious backdoors, in this work, we propose the problem of Backdoor Detection in a multi-agent competitive reinforcement learning system, with the objective of detecting Trojan agents as well as the corresponding potential trigger actions, and further trying to mitigate their Trojan behavior.

Machine Unlearning reinforcement-learning +2

AEVA: Black-box Backdoor Detection Using Adversarial Extreme Value Analysis

1 code implementation ICLR 2022 Junfeng Guo, Ang Li, Cong Liu

We approach this problem from the optimization perspective and show that the objective of backdoor detection is bounded by an adversarial objective.

Adv-Makeup: A New Imperceptible and Transferable Attack on Face Recognition

1 code implementation7 May 2021 Bangjie Yin, Wenxuan Wang, Taiping Yao, Junfeng Guo, Zelun Kong, Shouhong Ding, Jilin Li, Cong Liu

Deep neural networks, particularly face recognition models, have been shown to be vulnerable to both digital and physical adversarial examples.

Adversarial Attack Face Generation +2

Neural Mean Discrepancy for Efficient Out-of-Distribution Detection

no code implementations CVPR 2022 Xin Dong, Junfeng Guo, Ang Li, Wei-Te Ting, Cong Liu, H. T. Kung

Based upon this observation, we propose a novel metric called Neural Mean Discrepancy (NMD), which compares neural means of the input examples and training data.

General Classification Out-of-Distribution Detection +1

PredCoin: Defense against Query-based Hard-label Attack

no code implementations4 Feb 2021 Junfeng Guo, Yaswanth Yadlapalli, Thiele Lothar, Ang Li, Cong Liu

PredCoin poisons the gradient estimation step, an essential component of most QBHL attacks.

Hard-label Attack

PoisHygiene: Detecting and Mitigating Poisoning Attacks in Neural Networks

no code implementations24 Mar 2020 Junfeng Guo, Ting Wang, Cong Liu

Being able to detect and mitigate poisoning attacks, typically categorized into backdoor and adversarial poisoning (AP), is critical in enabling safe adoption of DNNs in many application domains.

Data Poisoning

PhysGAN: Generating Physical-World-Resilient Adversarial Examples for Autonomous Driving

no code implementations CVPR 2020 Zelun Kong, Junfeng Guo, Ang Li, Cong Liu

We compare PhysGAN with a set of state-of-the-art baseline methods including several of our self-designed ones, which further demonstrate the robustness and efficacy of our approach.

Autonomous Driving Image Classification

Cannot find the paper you are looking for? You can Submit a new open access paper.