Microsoft Defender Enhances Network Protection Against Malicious Domains

• •Microsoft Defender's network protection now blocks connections to malicious sites.
• •Custom indicators can be configured to enhance protection against specific threats.
• •The updates apply to both Microsoft and non-Microsoft browsers.

On October 19, 2026, Microsoft announced enhancements to its Defender network protection capabilities. The updates aim to prevent connections to malicious or suspicious sites, including phishing scams and harmful downloads. This feature extends Microsoft Defender SmartScreen's functionality to block outbound HTTP(S) traffic to low-reputation sources across various browsers and applications. The enhancements also allow for visibility and blocking of indicators of compromise (IOCs) when integrated with Endpoint detection and response. Organizations can configure custom indicators to block specific domains or hostnames. The updates are applicable to Microsoft Defender Antivirus and are designed to reduce the attack surface of devices. No specific CVEs or details were mentioned in the articles.