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Chengyu Song

10 accepted papers

2025

HEAL: An Empirical Study on Hallucinations in Embodied Agents Driven by Large Language Models

EMNLP 2025

Large language models (LLMs) are increasingly being adopted as the cognitive core of embodied agents. However, inherited hallucinations, which stem from failures to ground user instructions in the observed physical environment, can lead to navigation errors, such as searching for a refrigerator that

Cited by 0SourcePDFScholar
2025

Layer-wise Alignment: Examining Safety Alignment Across Image Encoder Layers in Vision Language Models

ICML 2025spotlight

Vision-language models (VLMs) have improved significantly in their capabilities, but their complex architecture makes their safety alignment challenging. In this paper, we reveal an uneven distribution of harmful information across the intermediate layers of the image encoder and show that skipping…

Cited by 0SourcePDFScholar
2024

Can Textual Unlearning Solve Cross-Modality Safety Alignment?

EMNLP 2024finding

Recent studies reveal that integrating new modalities into large language models (LLMs), such as vision-language models (VLMs), creates a new attack surface that bypasses existing safety training techniques like supervised fine-tuning (SFT) and reinforcement learning with human feedback (RLHF). Whil…

Cited by 1SourcePDFScholar
2022

Blackbox Attacks via Surrogate Ensemble Search

NeurIPS 2022accept

Blackbox adversarial attacks can be categorized into transfer- and query-based attacks. Transfer methods do not require any feedback from the victim model, but provide lower success rates compared to query-based methods. Query attacks often require a large number of queries for success. To achieve…

2022

Context-Aware Transfer Attacks for Object Detection

AAAI 2022technical

Blackbox transfer attacks for image classifiers have been extensively studied in recent years. In contrast, little progress has been made on transfer attacks for object detectors. Object detectors take a holistic view of the image and the detection of one object (or lack thereof) often depends on ot…

2022

GAMA: Generative Adversarial Multi-Object Scene Attacks

NeurIPS 2022accept

The majority of methods for crafting adversarial attacks have focused on scenes with a single dominant object (e.g., images from ImageNet). On the other hand, natural scenes include multiple dominant objects that are semantically related. Thus, it is crucial to explore designing attack strategies th…

2022

Zero-Query Transfer Attacks on Context-Aware Object Detectors

CVPR 2022poster

Adversarial attacks perturb images such that a deep neural network produces incorrect classification results. A promising approach to defend against adversarial attacks on natural multi-object scenes is to impose a context-consistency check, wherein, if the detected objects are not consistent with a…

Cited by 30PDFScholar
2021

Adversarial Attacks on Black Box Video Classifiers: Leveraging the Power of Geometric Transformations

NeurIPS 2021poster

When compared to the image classification models, black-box adversarial attacks against video classification models have been largely understudied. This could be possible because, with video, the temporal dimension poses significant additional challenges in gradient estimation. Query-efficient black…

2021

Exploiting Multi-Object Relationships for Detecting Adversarial Attacks in Complex Scenes

ICCV 2021poster

Vision systems that deploy Deep Neural Networks (DNNs) are known to be vulnerable to adversarial examples. Recent research has shown that checking the intrinsic consistencies in the input data is a promising way to detect adversarial attacks (e.g., by checking the object co-occurrence relationships…

Cited by 33PDFScholar
2020

Connecting the Dots: Detecting Adversarial Perturbations Using Context Inconsistency

ECCV 2020poster

There has been a recent surge in research on adversarial perturbations that defeat Deep Neural Networks (DNNs); most of these attacks target object classifiers. Inspired by the observation that humans are able to recognize objects that appear out of place in a scene or along with other unlikely obje…

Cited by 52SourcePDFScholar