Source: https://msrc-blog.microsoft.com/blog/2021/03/multiple-security-updates-released-for-exchange-server/
** *MSRC ** / By ** MSRC Team ** / March 2, 2021 **
On March 2nd, we released several security updates for Microsoft Exchange Server to address vulnerabilities that are being used in ongoing attacks. Due to the critical nature of these vulnerabilities, we recommend that customers protect their organizations by applying the patches immediately to affected systems.
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