Microsoft has released a security update for Exchange Server 2019 and Exchange 2016 to close a vulnerability classified as "critical". Specifically, it concerns the vulnerability CVE-2020-16875:
A remote code execution vulnerability exists in Microsoft Exchange server due to improper validation of cmdlet arguments.
An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the System user. Exploitation of the vulnerability requires an authenticated user in a certain Exchange role to be compromised.The security update addresses the vulnerability by correcting how Microsoft Exchange handles cmdlet arguments.
Source: https://portal.msrc.microsoft.com/en-us/security-guidance/advisory/CVE-2020-16875
The corresponding updates can be downloaded here:
- Microsoft Exchange Server 2016 Cumulative Update 16
- Microsoft Exchange Server 2016 Cumulative Update 17
- Microsoft Exchange Server 2019 Cumulative Update 5
- Microsoft Exchange Server 2019 Cumulative Update 6
The security update will also be included in the next CU. Security updates should nevertheless be installed as soon as possible.
