Exchange must have the most current, approved Cumulative Update (CU) installed.

The organization (including any contractor to the organization) must promptly install security-relevant software updates (e.g., patches, service packs, CUs, hot fixes). Flaws discovered during security assessments, continuous monitoring, incident response activities, or information system error handling must also be addressed.

Open the Exchange Management Shell and enter the following command:

Get-ExchangeServer | Format-List Name, AdminDisplayVersion

If the value of "AdminDisplayVersion" does not return the most current, approved CU, this is a finding.

Install the most current, approved CU.