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Security Update For Exchange Server 2016 CU20 (KB5001779)

Security Update For Exchange Server 2016 CU20 (KB5001779)

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  • Version:


    Date Published:


    File Name:


    File Size:

    151.1 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 restarting your computer before installing a security update. Then follow these steps:
    1. Disable the anti-virus software.
    2. Open an elevated Command Prompt window (not PowerShell) as an administrator, like this:
      • Select Start and then enter cmd .
      • Right-click Command Prompt in the results and select Run as administrator .
      • If the User Account Control dialog box appears, select Yes and then Next .
    3. At the command prompt, enter the full path to the folder that contains the 'MSP file', then press 'Enter'.
      Note: Do not double-click the 'MSP file' to run it.
    4. When the installation is complete, re-enable the antivirus software and restart your computer. (The installation program may prompt you to restart.)

    If problems occur during or after this installation, please refer to Repair failed installations of Exchange Cumulative and Security updates before contacting Microsoft Support.

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