CyberNER: A Harmonized STIX Corpus for Cybersecurity Named Entity Recognition
Yasir Ech-Chammakhy, Anas Motii, Anass Rabii, Oussama Azrara, Jaafar Chbili
TL;DR
This work tackles the fragmentation of cybersecurity NER data by introducing CyberNER, a harmonized STIX 2.1–based corpus derived from CyNER, DNRTI, APTNER, and Attacker. It presents a principled schema harmonization methodology, mapping diverse source tags to 21 STIX entity types across 609,922 tokens, and demonstrates that naive concatenation of datasets severely degrades performance. Empirical results show a substantial relative F1 improvement of about 30% over the naive baseline when training on CyberNER, with strong cross-dataset generalization across diverse CTI domains. The authors publicly release CyberNER to provide a standardized benchmark for robust, interoperable cybersecurity NER models and outline future work on expanding datasets, ablation studies, and extending to relation extraction and knowledge graphs.
Abstract
Extracting structured intelligence via Named Entity Recognition (NER) is critical for cybersecurity, but the proliferation of datasets with incompatible annotation schemas hinders the development of comprehensive models. While combining these resources is desirable, we empirically demonstrate that naively concatenating them results in a noisy label space that severely degrades model performance. To overcome this critical limitation, we introduce CyberNER, a large-scale, unified corpus created by systematically harmonizing four prominent datasets (CyNER, DNRTI, APTNER, and Attacker) onto the STIX 2.1 standard. Our principled methodology resolves semantic ambiguities and consolidates over 50 disparate source tags into 21 coherent entity types. Our experiments show that models trained on CyberNER achieve a substantial performance gain, with a relative F1-score improvement of approximately 30% over the naive concatenation baseline. By publicly releasing the CyberNER corpus, we provide a crucial, standardized benchmark that enables the creation and rigorous comparison of more robust and generalizable entity extraction models for the cybersecurity domain.
