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             The Traffic Light Protocol (TLP) is a set of designations used to ensure that sensitive information is shared with the correct audience. It employs four colors to indicate different degrees of sensitivity and the corresponding sharing considerations to be applied by the recipient(s).
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+            <a href="https://pan-unit42.github.io/playbook_viewer/" target="_blank">Unit42 Playbook Viewer</a>
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+            The goal of the Playbook is to organize the tools, techniques, and procedures that an adversary uses into a structured format, which can be shared with others, and built upon. The frameworks used to structure and share the adversary playbooks are MITRE's ATT&CK Framework and STIX 2.0
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             <a href="https://www.sans.org/reading-room/whitepapers/analyst/who-039-s-cyberthreat-intelligence-how-35767" target="_blank">Who's Using Cyberthreat Intelligence and How?</a>