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Security Update For Exchange Server 2016 CU23 (KB5019758)

Security Update For Exchange Server 2016 CU23 (KB5019758)

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  • Version:


    Date Published:


    File Name:


    File Size:

    152.6 MB

    KB Articles:


    A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the System user. An attacker could then install programs; view, change, or delete data; or create new accounts.
  • Supported Operating Systems

    Windows Server 2016, Windows 10, Windows Server 2012 R2, Windows Server 2012, Windows 8.1

    Exchange Server 2016 System Requirements and Prerequisites
    For information about Exchange 2016 system requirements and prerequisites, see the following topics:
    Actual requirements will vary based on system configuration. For more detailed system requirements, please refer to the Exchange Server 2016 Technical Documentation Library.
  • We recommend that you restart your computer before you install a security update. Then, follow these steps:
    1. Temporarily disable any anti-virus software.
    2. To start the download, select the Download button, and then do one of the following:
    • To start the installation immediately, select Run.
    • To copy the download file to your computer for installation at a later time, select Save.
    Note: To change the display language for this webpage, open the Select Language list, and then select the language that you want.
    1. After the installation is completed, re-enable the antivirus software, and then restart your computer. (The installation program may prompt you to restart. We strongly recommend that you restart the computer even if you are not prompted to do this.)

    If problems occur during or after the installation, please see Repair failed installations of Exchange Cumulative and Security updates before you contact Microsoft Support.
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