REVIEW
LI Qindong, CHEN Xingshu, TANG Wenyi
Journal of Cybersecurity.
2023, 1(1):
59-80.
Cyber threat intelligence is the knowledge that can guide organizations to deal with current cyber threats through the timely collection of internal and external threat information related to the organizational cyber security and comprehensive analysis, which can greatly improve the efficiency of the organizational cyber security defense. One type of threat intelligence is produced by collecting the multiple threat information on the Internet and then analyzing it comprehensively, i.e., open source threat intelligence, which can identify and analyze potential cyber threats, malicious activities, and attack trends, etc., and it has extremely high application value. However, in the production process of open source threat intelligence, it is necessary to overcome the difficulties of unstructured expression of intelligence, heterogeneity of expression among multiple sources of intelligence, and conflict of intelligence content, which attracts the attention of academia and industry. In view of this, recent cyber threat intelligence industry reports, white papers and academic results are first deeply studied, summarizing the open source threat intelligence production and application framework. Wherein, In the open source threat intelligence production process, the reliability of the intelligence is first assessed, which is also responsible for extracting intelligence from unstructured threat information, expression structure and content conflicts that exist between multiple sources of intelligence, and the intelligence application covers the entire defense life cycle of threat hunting, emergency response, and threat attribution. Hence, existing research results are organized and summarized from the aspects of threat intelligence extraction, intelligence conflict processing and intelligence application. Specifically, the existing research results first evaluate the quality of intelligence from both qualitative and quantitative perspectives,and multiple types of intelligence from multiple information sources through various techniques are extracted, but the extraction types and intelligence sources are mostly customized and one-sided. There are fewer research results on heterogeneous intelligence redundancy, while the intelligence inconsistency has received more and more attention, but most of them focus on the inconsistency detection of non-semantic intelligence, such as vulnerability affected product and intelligence disclosure time. Researchers have also focused on the related application of produced threat intelligence, but have not considered the integrity of the produced threat intelligence. Finally, the future research trends of open source threat intelligence production and application are given in this paper, including to the automated threat information comprehensive extraction, semantic threat information alignment and inconsistency research, intelligence integrity enhancement research based on existing knowledge, and research on intelligence application automation technology. By sorting out and analyzing the existing research overview of open source threat intelligence production and application, the development of China’s open source threat intelligence production and application is promoted,and the improvement of the overall defense capability of network security is realized.