Exposing Privacy Risks in Graph Retrieval-Augmented Generation

Jiale Liu, Jiahao Zhang, Suhang Wang


Abstract
Retrieval-Augmented Generation (RAG) is a powerful technique for enhancing Large Language Models (LLMs) with external, up-to-date knowledge. Graph RAG has emerged as an advanced paradigm that leverages graph-based knowledge structures to provide more coherent and contextually rich answers. However, the move from plain document retrieval to structured graph traversal introduces new, under-explored privacy risks. This paper investigates the data extraction vulnerabilities of the Graph RAG systems. We design and execute tailored data extraction attacks to probe their susceptibility to leaking both raw text and structured data, such as entities and their relationships. Our findings reveal a critical trade-off: while Graph RAG systems may reduce raw text leakage, they are significantly more vulnerable to the extraction of structured entity and relationship information. We also explore potential defense mechanisms to mitigate these novel attack surfaces. This work provides a foundational analysis of the unique privacy challenges in Graph RAG and offers insights for building more secure systems.
Anthology ID:
2026.findings-acl.899
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
18073–18093
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URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.899/
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Bibkey:
Cite (ACL):
Jiale Liu, Jiahao Zhang, and Suhang Wang. 2026. Exposing Privacy Risks in Graph Retrieval-Augmented Generation. In Findings of the Association for Computational Linguistics: ACL 2026, pages 18073–18093, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Exposing Privacy Risks in Graph Retrieval-Augmented Generation (Liu et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.899.pdf
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