collaborators

6 papers

cs.AI2026

Who Built This Model? Tracing LLM Lineage via Spectral Fingerprints in Weight Space

Yiwei Chen, Bingqi Shang, Sijia Liu

Open-weight large language models (LLMs) are increasingly developed through complex, multi-stage pipelines, leading to intricate lineage relationships that reflect model origin, ow…

cs.CR2026

Data-Centric Benchmarking of Exploit Generation in LLMs: Understanding the Impact of Fine-Tuning

Yiwei Chen, Lichi Li, Kai Cheung +2

We study the task of CVE-conditioned exploit generation, where a model drafts proof-of-concept (PoC) exploits given software vulnerability context. We adopt a data-centric approach…

cs.LG2026

Unlearning Isn't Invisible: Detecting Unlearning Traces in LLMs from Model Outputs

Yiwei Chen, Soumyadeep Pal, Yimeng Zhang +2

Machine unlearning (MU) for large language models (LLMs), commonly referred to as LLM unlearning, seeks to remove specific undesirable data or knowledge from a trained model, while…

cs.AI2026

Safety Mirage: How Spurious Correlations Undermine VLM Safety Fine-Tuning and Can Be Mitigated by Machine Unlearning

Yiwei Chen, Yuguang Yao, Yihua Zhang +3

Recent vision language models (VLMs) have made remarkable strides in generative modeling with multimodal inputs, particularly text and images. However, their susceptibility to gene…

cs.LG2026

Leak@: Unlearning Does Not Make LLMs Forget Under Probabilistic Decoding

Hadi Reisizadeh, Jiajun Ruan, Yiwei Chen +3

Unlearning in large language models (LLMs) is critical for regulatory compliance and for building ethical generative AI systems that avoid producing private, toxic, illegal, or cop…

cs.LG2025

Forgetting to Forget: Attention Sink as A Gateway for Backdooring LLM Unlearning

Bingqi Shang, Yiwei Chen, Yihua Zhang +2

Large language model (LLM) unlearning has become a critical mechanism for removing undesired data, knowledge, or behaviors from pre-trained models while retaining their general uti…