A Novel Trust Taxonomy for Shared Cyber Threat Intelligence

Table 3

Attribute reasoning.

Attribute	Value	Reasoning
Sharing Activity	9%	The number of CTI contributions may not be a direct indicator for trust. Nevertheless, the activity may signal the stakeholder whether someone is a free-rider or actively interested in a collaboration.
Stakeholder Rating	36%	The rating of the stakeholder received a higher contribution to the overall trust because other stakeholders may evaluate the peer’s trustworthiness based on the quality of the information and the conduct after receiving the information, i.e., whether the stakeholder conformed to secrecy labeling.
Same Source	18%	Transparency regarding where the intelligence comes from is a valuable contribution to the overall trust result, for instance, whether the sharing stakeholder also produced the intelligence or forwarded it from another unknown source.
Same Industry	37%	The same industry parameter received the highest value of all four attributes. Being inside the same industry sector, i.e., finance, retail, or manufacturing, automatically increases the trust amongst stakeholders.