Taeheon Kim
2025
Representation Bending for Large Language Model Safety
Ashkan Yousefpour
|
Taeheon Kim
|
Ryan Sungmo Kwon
|
Seungbeen Lee
|
Wonje Jeung
|
Seungju Han
|
Alvin Wan
|
Harrison Ngan
|
Youngjae Yu
|
Jonghyun Choi
Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Large Language Models (LLMs) have emerged as powerful tools, but their inherent safety risks – ranging from harmful content generation to broader societal harms – pose significant challenges. These risks can be amplified by the recent adversarial attacks, fine-tuning vulnerabilities, and the increasing deployment of LLMs in high-stakes environments. Existing safety-enhancing techniques, such as fine-tuning with human feedback or adversarial training, are still vulnerable as they address specific threats and often fail to generalize across unseen attacks, or require manual system-level defenses. This paper introduces RepBend, a novel approach that fundamentally disrupts the representations underlying harmful behaviors in LLMs, offering a scalable solution to enhance (potentially inherent) safety. RepBend brings the idea of activation steering – simple vector arithmetic for steering model’s behavior during inference – to loss-based fine-tuning. Through extensive evaluation, RepBend achieves state-of-the-art performance, outperforming prior methods such as Circuit Breaker, RMU, and NPO, with up to 95% reduction in attack success rates across diverse jailbreak benchmarks, all with negligible reduction in model usability and general capabilities.
Search
Fix author
Co-authors
- Jonghyun Choi 1
- Seungju Han 1
- Wonje Jeung 1
- Ryan Sungmo Kwon 1
- Seungbeen Lee 1
- show all...
Venues
- acl1