Hafnium Attack: Am I impacted? What should I do?

A threat actor called Hafnium is actively exploiting zero-day vulnerabilities in on-premises Microsoft Exchange servers, exposing thousands of organizations worldwide. Patching is an essential first step in stopping this attack – however that does not mean you are protected. You also need to investigate for indicators of attack and compromise, as an adversary may have already exploited these vulnerabilities. Patching is not sufficient if you are compromised; remediation is required.