English

Pruning for Protection: Increasing Jailbreak Resistance in Aligned LLMs Without Fine-Tuning

Machine Learning 2024-11-01 v3 Artificial Intelligence Computation and Language Cryptography and Security

Abstract

This paper investigates the impact of model compression on the way Large Language Models (LLMs) process prompts, particularly concerning jailbreak resistance. We show that moderate WANDA pruning can enhance resistance to jailbreaking attacks without fine-tuning, while maintaining performance on standard benchmarks. To systematically evaluate this safety enhancement, we introduce a dataset of 225 harmful tasks across five categories. Our analysis of LLaMA-2 Chat, Vicuna 1.3, and Mistral Instruct v0.2 reveals that pruning benefits correlate with initial model safety levels. We interpret these results by examining changes in attention patterns and perplexity shifts, demonstrating that pruned models exhibit sharper attention and increased sensitivity to artificial jailbreak constructs. We extend our evaluation to the AdvBench harmful behavior tasks and the GCG attack method. We find that LLaMA-2 is much safer on AdvBench prompts than on our dataset when evaluated with manual jailbreak attempts, and that pruning is effective against both automated attacks and manual jailbreaking on Advbench.

Keywords

Cite

@article{arxiv.2401.10862,
  title  = {Pruning for Protection: Increasing Jailbreak Resistance in Aligned LLMs Without Fine-Tuning},
  author = {Adib Hasan and Ileana Rugina and Alex Wang},
  journal= {arXiv preprint arXiv:2401.10862},
  year   = {2024}
}

Comments

Proceedings of the 7th BlackboxNLP Workshop: Analyzing and Interpreting Neural Networks for NLP

R2 v1 2026-06-28T14:21:53.533Z