KLA12103
ACE vulnerabilities in Microsoft Exchange Server

Remote code execution vulnerabilities were found in Microsoft Exchange Server. Malicious users can exploit this vulnerability to execute arbitrary code.

This vulnerability can be exploited by the following malware:

https://threats.kaspersky.com/en/threat/Exploit.Script.CVE-2021-26855/

Public exploits exist for this vulnerability.

Microsoft Exchange Server 2019 Cumulative Update 8
Microsoft Exchange Server 2013 Cumulative Update 23
Microsoft Exchange Server 2016 Cumulative Update 18
Microsoft Exchange Server 2010 Service Pack 3
Microsoft Exchange Server 2016 Cumulative Update 19
Microsoft Exchange Server 2019 Cumulative Update 7

Install necessary updates from the KB section, that are listed in your Windows Update (Windows Update usually can be accessed from the Control Panel)

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