October 2021 Exchange Server Security Updates
Overview
Microsoft recently released their October 2021 Exchange Server Security Updates, addressing a vulnerability impacting Microsoft Exchange Server 2019 and Exchange Server 2016. This article provides an overview of the security patches and their associated security advisories.
What is the Vulnerability?
The vulnerability, identified as CVE-2021-26855, is a remote code execution (RCE) vulnerability that exists in Microsoft Exchange Server when the server fails to properly create unique keys at install time. This vulnerability can be exploited by an attacker to gain access to an Exchange Server and execute malicious code. Microsoft has provided information on how to identify if your Exchange Server is vulnerable and how to address any vulnerabilities.
What Security Patches Were Released?
Microsoft released security patches for Exchange Server 2019 and Exchange Server 2016 on October 13, 2021. The patches are available for download through the Microsoft Security Update Guide.
How to Protect Your Exchange Server
Microsoft has provided guidance on the best practices for protecting Exchange Server from the CVE-2021-26855 vulnerability. The following steps should be taken to ensure the security of your Exchange Server:
* Update Exchange Server 2019 to the latest Cumulative Update (CU).
* Update Exchange Server 2016 to the latest Cumulative Update (CU).
* Ensure that Exchange Server is running the latest version of the Microsoft Exchange Server Security Update.
* Review the Exchange Server security best practices and configure the server according to the recommendations.
* Ensure that the Windows OS is updated to the latest version.
* Perform regular audits of Exchange Server to identify any security issues or misconfigurations.
* Enable the audit logging feature on Exchange Server to track user activity.
Conclusion
Microsoft recently released their October 2021 Exchange Server Security Updates, addressing an important vulnerability impacting Microsoft Exchange Server 2019 and Exchange Server 2016. It is important to ensure that Exchange Server is updated with the latest security patches and that the Windows OS is also updated to the latest version. Additionally, best practices such as regular audits and audit logging should be implemented to ensure that your Exchange Server is secure.
References:
Released: October 2021 Exchange Server Security Updates
