Security intelligence updates for Microsoft Defender Antivirus and other Microsoft antimalware

Microsoft continually updates security intelligence in antimalware products to cover the latest threats and to constantly tweak detection logic, enhancing the ability of Microsoft Defender Antivirus and other Microsoft antimalware solutions to accurately identify threats. This security intelligence works directly with cloud-based protection to deliver fast and powerful AI-enhanced, next-generation protection.

Microsoft security intelligence updates include software that incorporates material from third parties. Third-party notices and information

Automatic updates

To help ensure your antimalware solution detects the latest threats, get updates automatically as part of Windows Update. If you are having problems with Windows Update, use the troubleshooter.

If you don’t already use Microsoft Defender Antivirus, learn how to turn it on.

Trigger an update

A manually triggered update immediately downloads and applies the latest security intelligence. This process might also address problems with automatic updates. Microsoft Defender Antivirus and other Microsoft antimalware solutions provide a way to manually trigger an update.

In Windows 10, select Check for updates in the Windows Security Virus & threat protection screen to check for the latest updates.

Enterprise administrators can also push updates to devices in their network. To clear the current cache and trigger an update, use a batch script that runs the following commands as an administrator:

Manually download the update

You can manually download the latest update.

Latest security intelligence update

The latest security intelligence update is:

• Version: 1.335.1094.0
• Engine Version: 1.1.18000.5
• Platform Version: 4.18.2103.7
• Released: 4/17/2021 11:07:05 PM
• Documentation: Release notes

You need to download different security intelligence files for different products and platforms. Select the version that matches your Windows operating system or the environment where you will apply the update.

Note: Starting on Monday October 21, 2019, the Security intelligence update packages will be SHA2 signed.
Please make sure you have the necessary update installed to support SHA2 signing, see 2019 SHA-2 Code Signing Support requirement for Windows and WSUS.

Antimalware solution	Definition version
Microsoft Defender Antivirus for Windows 10 and Windows 8.1	32-bit | 64-bit | ARM
Microsoft Security Essentials	32-bit | 64-bit
Windows Defender in Windows 7 and Windows Vista	32-bit | 64-bit
Microsoft Diagnostics and Recovery Toolset (DaRT)	32-bit | 64-bit
System Center 2012 Configuration Manager	32-bit | 64-bit
System Center 2012 Endpoint Protection	32-bit | 64-bit
Windows Intune	32-bit | 64-bit

The links point to an executable file named mpam-fe.exe , mpam-feX64.exe , or mpas-fe.exe (used by older antispyware solutions). Simply launch the file to manually install the latest security intelligence.

End of life for Microsoft Forefront Client Security was on July 14, 2015. Customers are encouraged to migrate to System Center Endpoint Protection. For more information, visit the Microsoft support lifecycle website.

Network Inspection System updates

The following products leverage Network Inspection System (NIS) updates:

• Microsoft Security Essentials
• Forefront Endpoint Protection
• System Center 2012 Endpoint Protection

These updates are designed to protect you from network threats, including exploits as they are transmitted. Check the version of the Antimalware Client component on your security software and download the right version of the NIS updates for your platform.

Security update for Windows 10, version 1607, 1703, 1709, 1803, 1809, 1903, 1909, Windows Server 2016 and Windows Server 2019: February 11, 2020

This standalone security update has been removed due to an issue affecting a sub-set of devices. It will not be re-offered from Windows Update, Windows Server Update Services (WSUS) or Microsoft Update Catalog. Note Removal of this standalone security update does not affect successful installation or any changes within any other February 11, 2020 security updates, including Latest Cumulative Update (LCU), Monthly Rollup or Security Only update.

Summary

This security update makes improvements to the supported Windows 10 versions listed in the «Applies to» section. Key changes include the following:

Addresses an issue in which a third-party Unified Extensible Firmware Interface (UEFI) boot manager might expose UEFI-enabled computers to a security vulnerability.

To learn more about this security update, see Microsoft Common Vulnerabilities and Exposures.

Known Issues

Using the “Reset this PC” feature, also called “Push Button Reset” or PBR, might fail. You might restart into recovery with “Choose an option” at the top of the screen with various options or you might restart to desktop and receive the error “There was a problem resetting your PC”.

This standalone security update has been removed and will not be re-offered from Windows Update, Windows Server Update Services (WSUS) or Microsoft Update Catalog. Note This does not affect any other update, including Latest Cumulative Update (LCU), Monthly Rollup or Security Only update.

If you have installed this update and are experiencing this issue, the following steps should allow you to reset your device:

Select the start button or Windows Desktop Search and type update history and select View your Update history.

On the Settings/View update history dialog window, Select Uninstall Updates.

On the Installed Updates dialog window, find and select KB4524244 and select the Uninstall button.

Restart your device.

Upon restart use the “Reset this PC” feature and you should not encounter this issue.

We are working on an improved version of this update in coordination with our partners and will release it in a future update.

You might encounter issues trying to install or after installing KB4524244.

To help a sub-set of affected devices, this standalone security update has been removed and will not be re-offered from Windows Update, Windows Server Update Services (WSUS) or Microsoft Update Catalog. Note This does not affect any other update, including Latest Cumulative Update (LCU), Monthly Rollup or Security Only update.

If this update is installed and you are experiencing issues, you can uninstall this update.

Select the start button or Windows Desktop Search and type update history and select View your Update history.

On the Settings/View update history dialog window, Select Uninstall Updates.

On the Installed Updates dialog window, find and select KB4524244 and select the Uninstall button.

Restart your device.

We are working on an improved version of this update in coordination with our partners and will release it in a future update.

How to get this update

Important This standalone security update has been removed due to an issue affecting a sub-set of devices. It will not be re-offered from Windows Update, Windows Server Update Services (WSUS) or Microsoft Update Catalog. Note Removal of this standalone security update does not affect successful installation or any changes within any other February 11, 2020 security updates, including Latest Cumulative Update (LCU), Monthly Rollup or Security Only update.

Prerequisites

There are no prerequisites to apply this update.

Restart information

Your device does not have to restart when you apply this update. If you have Windows Defender Credential Guard (Virtual Secure Mode) enabled, your device will restart two times.

Update replacement information

This update does not replace any previously released update.

File information

Windows 10, version 1903 and Windows 10, version 1909

File attributes

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.

Windows 10, version 1809 and Windows Server 2019

File attributes

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.

Windows 10, version 1803

File attributes

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.

Windows 10, version 1709

File information

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.

Windows 10, version 1703

File attributes

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.

Windows 10, version 1607 and Windows Server 2016

File attributes

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.