Dear Valued DMC Customer;
During the week of March 1, we reached out to our customers who we were aware of that are running Microsoft Exchange Server on premises or Microsoft Hybrid Exchange server. We wanted to immediately convey information about the critical Security Update that needed to be applied due to a security vulnerability. We wanted to send out this communication to all our customers to ensure we did not miss anyone.
The two links below provide information about the security vulnerability and information about the security update.
The link below is from CISA (Cybersecurity and Infrastructure Security Agency branch of the US gov't).
https://us-cert.cisa.gov/ncas/alerts/aa21-062a
This link is Microsoft's official security blog post about it.
There’s also the official Exchange blog’s post about the security updates that were published to address the vulnerability:
If DMC can assist with immediate updates to your Exchange environment, or help to plan a migration to M365, please contact us.
