defense 2025

DAC-LoRA: Dynamic Adversarial Curriculum for Efficient and Robust Few-Shot Adaptation

Ved Umrajkar

0 citations · 21 references · arXiv

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Published on arXiv

2509.20792

Input Manipulation Attack

OWASP ML Top 10 — ML01

Key Finding

DAC-LoRA achieves substantial improvements in adversarial robustness over standard LoRA fine-tuning without significantly compromising clean accuracy on CLIP-based VLMs.

DAC-LoRA

Novel technique introduced


Vision-Language Models (VLMs) are foundational to critical applications like autonomous driving, medical diagnosis, and content moderation. While Parameter-Efficient Fine-Tuning (PEFT) methods like LoRA enable their efficient adaptation to specialized tasks, these models remain vulnerable to adversarial attacks that can compromise safety-critical decisions. CLIP, the backbone for numerous downstream VLMs, is a high-value target whose vulnerabilities can cascade across the multimodal AI ecosystem. We propose Dynamic Adversarial Curriculum DAC-LoRA, a novel framework that integrates adversarial training into PEFT. The core principle of our method i.e. an intelligent curriculum of progressively challenging attack, is general and can potentially be applied to any iterative attack method. Guided by the First-Order Stationary Condition (FOSC) and a TRADES-inspired loss, DAC-LoRA achieves substantial improvements in adversarial robustness without significantly compromising clean accuracy. Our work presents an effective, lightweight, and broadly applicable method to demonstrate that the DAC-LoRA framework can be easily integrated into a standard PEFT pipeline to significantly enhance robustness.


Key Contributions

  • DAC-LoRA: a dynamic adversarial curriculum framework that integrates adversarial training into LoRA-based PEFT, using progressively harder attacks guided by the First-Order Stationary Condition (FOSC)
  • TRADES-inspired loss adaptation for PEFT fine-tuning to balance clean accuracy and adversarial robustness
  • Demonstration that the curriculum principle is general and applicable to any iterative attack method within a standard PEFT pipeline

🛡️ Threat Analysis

Input Manipulation Attack

The paper's primary contribution is a defense against adversarial input manipulation attacks — specifically, adversarially training VLMs (CLIP) during LoRA fine-tuning using a progressively harder attack curriculum (FOSC-guided) and a TRADES-inspired loss to improve robustness against adversarial examples at inference time.


Details

Domains
visionmultimodal
Model Types
vlmtransformer
Threat Tags
white_boxinference_timedigital
Applications
vision-language modelsautonomous drivingmedical diagnosiscontent moderation