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arXiv · 2504.18375

Bandit on the Hunt: Dynamic Crawling for Cyber Threat Intelligence

Philipp Kuehn·Dilara Nadermahmoodi·Markus Bayer·Christian Reuter
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Abstract

Public information contains valuable Cyber Threat Intelligence (CTI) that is used to prevent future attacks. While standards exist for sharing this information, much appears in non-standardized news articles or blogs. Monitoring online sources for threats is time-consuming and source selection is uncertain. Current research focuses on extracting Indicators of Compromise from known sources, rarely addressing new source identification. This paper proposes a CTI-focused crawler using multi-armed bandit (MAB) and various crawling strategies. It employs SBERT to identify relevant documents while dynamically adapting its crawling path. Our system ThreatCrawl achieves a harvest rate exceeding 25% and expands its seed by over 300% while maintaining topical focus. Additionally, the crawler identifies previously unknown but highly relevant overview pages, datasets, and domains.

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Philipp Kuehn, Dilara Nadermahmoodi, Markus Bayer, Christian Reuter. 2025-04-25. Bandit on the Hunt: Dynamic Crawling for Cyber Threat Intelligence. https://arxiv.org/abs/2504.18375

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