defense 2025

RAGRank: Using PageRank to Counter Poisoning in CTI LLM Pipelines

Austin Jia , Avaneesh Ramesh , Zain Shamsi , Daniel Zhang , Alex Liu

0 citations · 30 references · arXiv

α

Published on arXiv

2510.20768

Data Poisoning Attack

OWASP ML Top 10 — ML02

Training Data Poisoning

OWASP LLM Top 10 — LLM03

Key Finding

RAGRank assigns lower authority scores to malicious injected documents while promoting trusted content, demonstrated quantitatively on MS MARCO and qualitatively on CTI feeds.

RAGRank

Novel technique introduced


Retrieval-Augmented Generation (RAG) has emerged as the dominant architectural pattern to operationalize Large Language Model (LLM) usage in Cyber Threat Intelligence (CTI) systems. However, this design is susceptible to poisoning attacks, and previously proposed defenses can fail for CTI contexts as cyber threat information is often completely new for emerging attacks, and sophisticated threat actors can mimic legitimate formats, terminology, and stylistic conventions. To address this issue, we propose that the robustness of modern RAG defenses can be accelerated by applying source credibility algorithms on corpora, using PageRank as an example. In our experiments, we demonstrate quantitatively that our algorithm applies a lower authority score to malicious documents while promoting trusted content, using the standardized MS MARCO dataset. We also demonstrate proof-of-concept performance of our algorithm on CTI documents and feeds.


Key Contributions

  • RAGRank: a PageRank-derived authority score that suppresses malicious documents and promotes trusted content in RAG corpora
  • Citation network construction using explicit citations, LLM-inferred citations, and claim-level entailment, augmented with time decay and author credibility
  • Quantitative evaluation on MS MARCO showing lower authority scores for injected malicious documents, plus proof-of-concept on CTI feeds

🛡️ Threat Analysis

Data Poisoning Attack

The attack being defended against is injecting malicious documents (falsified threat reports, manipulated IoCs, poisoned mitigation advice) into the RAG retrieval corpus — a data poisoning attack on the knowledge base used at inference time. RAGRank is the proposed defense.


Details

Domains
nlp
Model Types
llm
Threat Tags
inference_timedigitalblack_box
Datasets
MS MARCO
Applications
cyber threat intelligencerag pipelinesllm-based security operations