Microsoft Defender Antivirus security intelligence January 2026

[harlan4096]

Stable channel updates:

• Antimalware Client Version: 4.18.26020.6
  
• Engine Version: 1.1.26020.3
  

Enhancements and features​

• Improved the network protection feature to promptly release closed connections and reduce unnecessary memory usage.
  
• Fixed an issue where the Get-MpComputerStatus PowerShell cmdlet could fail after updates due to a configuration mismatch.
  
• Improved performance for Network Response Intelligence (NRI) by reducing CPU usage during high-volume asynchronous message processing.
  
• Added support for AMSI path exclusions for Exchange Server so configured path exclusions are now correctly evaluated during AMSI scanning for Exchange workloads.
  
• Improved policy refresh behavior for device control by updating default policy and Azure AD refresh intervals to reduce retry frequency.
  

Microsoft Defender for Endpoint release notes - Microsoft Defender for Endpoint