An organization has tasked a network administrator with analyzing a recent cyberattack on the system. They want to understand the attack methodology used by the attackers.

Which framework can the administrator use to access a database of known tactics, techniques, and procedures $($TTPs$)$ used by different threat actor groups?

Diamond Model of Intrusion Analysis

Open Source Security Testing Methodology

Manual $($OSSTMM$)$

MITRE ATT&CK

Cyber kill chain