Cyber Threat Intelligence Repository of ATT&CK catalog expressed in STIX 2.0
ATT&CK is a catalog of techniques and tactics that describe post-compromise adversary behavior on typical enterprise IT environments. The core use cases involve using the catalog to analyze, triage, compare, describe, relate, and share post-compromise adversary behavior.
https://attack.mitre.org/wiki/Main_Page
Structured Threat Information Expression (STIX™) is a language and serialization format used to exchange cyber threat intelligence (CTI).
STIX enables organizations to share CTI with one another in a consistent and machine readable manner, allowing security communities to better understand what computer-based attacks they are most likely to see and to anticipate and/or respond to those attacks faster and more effectively.
STIX is designed to improve many different capabilities, such as collaborative threat analysis, automated threat exchange, automated detection and response, and more.