arXiv AI

Ultraconstructive Model Theory via Bounded Adversarial Finite Structures

arXiv:2608. 07534v1 Announce Type: cross Abstract: Ultraconstructive Model Theory (UCMT) replaces idealized satisfaction, at finite compu- tational scale, by bounded adversarial survival.

arXiv Machine Learning
Oct 8

Open-Weight LLM Fine-Tuning Defenses are Susceptible to Simple Attacks

The paper examines the vulnerability of open‑weight large language model safeguards that aim to block harmful usage by assuming new harmful behavior arises only through fine‑tuning. It demonstrates that simple, low‑cost attacks—abliteration and prefilling—can significantly increase attack success rates across multiple benchmarks, and proposes an abliteration‑resistant tuning (ART) method that mitigates these attacks. The study shows that safeguarding defenses must be evaluated against a broader range of attack strategies beyond fine‑tuning.

By Kevin Kuo, Virginia Smith, Chhavi Yadav
arXiv Machine Learning
Oct 23

Does More Compute Make Every Adversarial Attack Transferable?

The paper investigates whether increased computational resources for an attacker can make adversarial attacks transferable across all defenders. It finds that for classification tasks, a quadratic resource gap guarantees either a transferable attack or a defense, whereas for generative tasks this guarantee fails. The authors also show that a defense that adds computation after seeing the input can be provably stronger than any fixed-model defense, suggesting that inference-time compute can enhance robustness.

By Greg Gluch, Shafi Goldwasser, Anastasiia Struss
arXiv AI
5d ago

AnchorRep: Defending LLMs Against Cross-Model Adversarial Transfer via Representation Repulsion

AnchorRep is a lightweight LoRA adapter that defends large language models (LLMs) against cross-model adversarial transfer by repelling internal representations of harmful prompts away from those of a frozen anchor model. It requires only a small set of harmful prompts for training and achieves a cross‑model attack success rate of 1.1% across five models and four architectural families. Compared to existing defenses, AnchorRep avoids high costs such as up to 77% degenerate benign output or 18% over‑refusal, and introduces the Benign Garble Rate metric to capture these failures.

By Gal Wertheizer, Rom Himelstein, Tomer Peretz, Avi Mendelson
arXiv Machine Learning
Jul 10

Communication-Efficient Byzantine-Robust Federated Conformal Prediction via Partial Model Sharing

arXiv:2602. 18396v2 Announce Type: replace Abstract: We propose PRISM-FCP (Partial shaRing and robust calIbration with Statistical Margins for Federated Conformal Prediction), a communication-efficient Byzantine-robust federated conformal prediction framework that uses partial model sharing to mitigate stochastic model-poisoning attacks during training and histogram-based filtering to mitigate adversarial calibration submissions.

By Ehsan Lari, Reza Arablouei, Stefan Werner