Publications

"Beyond Age-Based Restrictions: Rethinking Children's Online Safety Through Comparing Parent–Child Perspectives of Risks in User-Generated Content Games"

Ruchi Panchanadikar, Yang Hu*, Keyan Guo*, Amelia L Hall, Hongxin Hu, Nishant Vishwamitra, Guo Freeman

ACM CHI Conference on Human Factors in Computing Systems (CHI), 2026

"HVGuard: Utilizing Multimodal Large Language Models for Hateful Video Detection"

Yiheng Jing, Mingming Zhang, Yong Zhuang, Jiacheng Guo, Juan Wang, Xiaoyang Xu, Wenzhe Yi, Keyan Guo, Hongxin Hu

Conference on Empirical Methods in Natural Language Processing (EMNLP), 2025

"JBShield: Defending Large Language Models from Jailbreak Attacks through Activated Concept Analysis and Manipulation"

Shenyi Zhang, Yuchen Zhai, Keyan Guo, Hongxin Hu, Shengnan Guo, Zheng Fang, Lingchen Zhao, Chao Shen, Cong Wang, Qian Wang

34th USENIX Security Symposium (USENIX Security), 2025

"I know what you MEME! Understanding and Detecting Harmful Memes with Multimodal Large Language Models"

Yong Zhuang*, Keyan Guo*, Juan Wang, Yiheng Jing, Xiaoyang Xu, Wenzhe Yi, Mengda Yang, Bo Zhao, Hongxin Hu

Network and Distributed System Security Symposium (NDSS), 2025

"Moderating Illicit Online Image Promotion for Unsafe User-Generated Content Games Using Large Vision-Language Models"

Keyan Guo, Ayush Utkarsh, Wenbo Ding, Isabelle Ondracek, Ziming Zhao, Guo Freeman, Nishant Vishwamitra, Hongxin Hu

33rd USENIX Security Symposium (USENIX Security), 2024

"Moderating New Waves of Online Hate with Chain-of-Thought Reasoning in Large Language Models"

Nishant Vishwamitra*, Keyan Guo*, Farhan Tajwar Romit, Isabelle Ondracek, Long Cheng, Ziming Zhao, Hongxin Hu

45th IEEE Symposium on Security and Privacy (IEEE S&P), 2024

"An Investigation of Large Language Models for Real-World Hate Speech Detection"

Keyan Guo, Alexander Hu, Jaden Mu, Ziheng Shi, Ziming Zhao, Nishant Vishwamitra, Hongxin Hu

22nd IEEE International Conference on Machine Learning and Applications (ICMLA), 2023

"Understanding and Analyzing COVID-19-related Online Hate Propagation Through Hateful Memes Shared on Twitter"

Nishant Vishwamitra*, Keyan Guo*, Song Liao, Jaden Mu, Zheyuan Ma, Long Cheng, Ziming Zhao, Hongxin Hu

IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining (ASONAM), 2023

"AI-Cybersecurity Education Through Designing AI-based Cyberharassment Detection Lab"

Ebuka Okpala, Nishant Vishwamitra, Keyan Guo, Song Liao, Long Cheng, Hongxin Hu, Yongkai Wu, Xiaohong Yuan, Jeannette Wade, Sajad Khorsandroo

IEEE Frontiers in Education Conference (FIE), 2023

"Understanding and Measuring Robustness of Vision and Language Multimodal Models"

Nishant Vishwamitra, Keyan Guo, Hongxin Hu, Ziming Zhao, Long Cheng, Feng Luo

International Conference on Secure Knowledge Management (SKM), 2023

"Exploring Vulnerabilities in Voice Command Skills for Connected Vehicles"

Wenbo Ding, Song Liao, Keyan Guo, Ziming Zhao, Hongxin Hu

EAI International Conference on Security and Privacy in Cyber-Physical Systems and Smart Vehicles (EAI SmartSP), 2023

"Understanding the Generalizability of Hateful Memes Detection Models Against COVID-19-related Hateful Memes"

Keyan Guo, Wentai Zhao, Jaden Mu, Nishant Vishwamitra, Ziming Zhao, Hongxin Hu

21st IEEE International Conference on Machine Learning and Applications (ICMLA), 2022

"Understanding the Effects of Paint Colors on LiDAR Point Cloud Intensities"

Shaik Sabiha, Keyan Guo, Foad Hajiaghajani, Chunming Qiao, Hongxin Hu, Ziming Zhao

Workshop on Automotive and Autonomous Vehicle Security (AutoSec), 2022