Guardado en:
Detalles Bibliográficos
Autores principales: Chen, Xiaoyi, Wang, Haoyuan, Tang, Siyuan, Liu, Sijia, Su, Liya, Wang, XiaoFeng, Tang, Haixu
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:https://arxiv.org/abs/2604.22076
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866914503547944960
author Chen, Xiaoyi
Wang, Haoyuan
Tang, Siyuan
Liu, Sijia
Su, Liya
Wang, XiaoFeng
Tang, Haixu
author_facet Chen, Xiaoyi
Wang, Haoyuan
Tang, Siyuan
Liu, Sijia
Su, Liya
Wang, XiaoFeng
Tang, Haixu
contents Large language models (LLMs) often memorize private information during training, raising serious privacy concerns. While machine unlearning has emerged as a promising solution, its true effectiveness against privacy attacks remains unclear. To address this, we propose PrivUn, a new evaluation framework that systematically assesses unlearning robustness through three-tier attack scenarios: direct retrieval, in-context learning recovery, and fine-tuning restoration; combined with quantitative analysis using forgetting scores, association metrics, and forgetting depth assessment. Our study exposes significant weaknesses in current unlearning methods, revealing two key findings: 1) unlearning exhibits gradient-driven ripple effects: unlike traditional forgetting which follows semantic relations (e.g., knowledge graphs), privacy unlearning propagates across latent gradient-based associations; and 2) most methods suffer from shallow forgetting, failing to remove private information distributed across multiple deep model layers. To validate these insights, we explore two strategies: association-aware core-set selection that leverages gradient similarity, and multi-layer deep intervention through representational constraints. These strategies represent a paradigm shift from shallow forgetting to deep forgetting.
format Preprint
id arxiv_https___arxiv_org_abs_2604_22076
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle PrivUn: Unveiling Latent Ripple Effects and Shallow Forgetting in Privacy Unlearning
Chen, Xiaoyi
Wang, Haoyuan
Tang, Siyuan
Liu, Sijia
Su, Liya
Wang, XiaoFeng
Tang, Haixu
Machine Learning
Computation and Language
Large language models (LLMs) often memorize private information during training, raising serious privacy concerns. While machine unlearning has emerged as a promising solution, its true effectiveness against privacy attacks remains unclear. To address this, we propose PrivUn, a new evaluation framework that systematically assesses unlearning robustness through three-tier attack scenarios: direct retrieval, in-context learning recovery, and fine-tuning restoration; combined with quantitative analysis using forgetting scores, association metrics, and forgetting depth assessment. Our study exposes significant weaknesses in current unlearning methods, revealing two key findings: 1) unlearning exhibits gradient-driven ripple effects: unlike traditional forgetting which follows semantic relations (e.g., knowledge graphs), privacy unlearning propagates across latent gradient-based associations; and 2) most methods suffer from shallow forgetting, failing to remove private information distributed across multiple deep model layers. To validate these insights, we explore two strategies: association-aware core-set selection that leverages gradient similarity, and multi-layer deep intervention through representational constraints. These strategies represent a paradigm shift from shallow forgetting to deep forgetting.
title PrivUn: Unveiling Latent Ripple Effects and Shallow Forgetting in Privacy Unlearning
topic Machine Learning
Computation and Language
url https://arxiv.org/abs/2604.22076