Sharing of Cyber Threat Intelligence (CTI) has turned out to be an indispensable pillar of the modern cybersecurity landscape, it is enabling organizations to defend against the evolving threats. In this white paper, we will discuss the strategies to optimize the sharing of threat intelligence across multiple security platforms in the enterprise and community context. We will observe the current standards and practices, like Structured Threat Information eXpression (STIX) and trusted Automated Exchange of Indicator Information (TAXII) protocols, and also examine the role of these standards in integrating the Threat Intelligence Platforms (TIPs) with Security Information and Event Management (SIEM) systems. We will observe the impact of threat intelligence exchange through real-world case studies and how the cybersecurity attacks are mitigated, along with the challenges that are encountered (e.g., technical integration gaps, data overload, trust and privacy issues). We will also discuss the limitations in the current approaches, which include the inconsistent adoption of the standards, there is a prevalence of indicators with low context, and siloed systems that impede the information flow. The landscape of the emerging solutions, the future directions will be explored, machine learning prioritized to reduce the false positives, a decentralized sharing architecture by leveraging blockchain and federated learning for privacy, and also trust frameworks to incentivize collaboration. Through addressing the present challenges and leveraging the advanced technologies, organizations will be able to create a unified and effective threat intelligence sharing ecosystem that will strengthen the collective cyber defense.

Cyber Threat Intelligence, Threat Information Sharing, STIX/TAXII (Structured Threat Information eXpression/Trusted Automated eXchange of Intelligence Information), Threat Intelligence Platform (TIP), Security Information and Event Management (SIEM), Machine Learning, Blockchain, Federated Learning, Information Sharing and Analysis Center (ISAC), Cybersecurity Collaboration

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