The quality of Cyber Threat Intelligence (CTI) has a profound impact on the efficacy of an organization’s defense against cyber threats, directly influencing its ability to safeguard critical assets and sensitive data. Despite its critical importance, the domain of CTI quality remains a multifaceted and evolving field, often operating at the intersection of theory and practice. Many organizations recognize the need for high-quality intelligence but may struggle to establish systematic processes for assessing and enhancing its quality.

Incident response "playbooks" are structured sets of operational procedures organizations use to instruct humans or machines on performing countermeasures against cybersecurity threats. These playbooks generally combine information about a given threat and organizational aspects relevant within the context of an organization. Both types of information are crucial for using, maintaining, and sharing playbooks across organizations as they ensure effectiveness and confidentiality. While practitioners show great interest in playbooks, their characteristics have not yet been thoroughly investigated from a research perspective. For this reason, we explore the topic by analyzing what is inside a playbook. Our approach consists of a comprehensive empirical assessment of available data (1217 playbooks), an online study with 147 participants, and final in-depth interviews with nine security professionals to consolidate and validate our findings. We notably find intrinsic ambiguities in the way practitioners and organizations define their playbooks. Furthermore, we notice that available playbooks cannot be used outright which might currently impair their wide use across different cybersecurity actors. As a result, we can conclude that organizations do "play it by the books" but individually define what is inside their playbooks and which areas of incident response they might address.

There are many mysteries surrounding sharing communities, mainly due to their hidden workings and the complexity of joining. Nevertheless, these communities are critical to the security ecosystem, so a more profound understanding is necessary. In addition, they face challenges such as building trust, communicating effectively, and addressing social problems.

Understanding and fending off attack campaigns against organizations, companies and individuals, has become a global struggle. As today's threat actors become more determined and organized, isolated efforts to detect and reveal threats are no longer effective. Although challenging, this situation can be significantly changed if information about security incidents is collected, shared and analyzed across organizations. To this end, different exchange data formats such as STIX, CyBOX, or IODEF have been recently proposed and numerous CERTs are adopting these threat intelligence standards to share tactical and technical threat insights. However, managing, analyzing and correlating the vast amount of data available from different sources to identify relevant attack patterns still remains an open problem.