Defender for endpoint – Web content filtering

Defender for Endpoint’s web content filtering is a crucial tool in countering attackers who frequently switch domains, especially when flagged as malicious. AiTM domains, often newly registered and short-lived, can be effectively managed using web content filtering in Microsoft Defender for Endpoint (MDE). Here’s how:

1. Blocking Newly Registered Domains:
   • Within the “uncategorized” category, you can block two specific subcategories:
     • Parked domains: Websites with no content or temporarily parked.
     • Newly Registered Domains: Domains registered in the past 30 days that haven’t been categorized yet.
2. Auditing and Policy Deployment:
   • Deploy a policy on a device group without selecting any category initially. This creates an audit-only policy, allowing you to review potential blocked events.
   • It’s advisable to run the audit mode for a few weeks before enabling the “uncategorized” categories. This cautious approach helps ensure that legitimate sites aren’t inadvertently blocked.
3. Custom Indicators for Flexibility:
   • Use custom indicators to permit specific websites when necessary. This provides flexibility in allowing access to particular sites even if they fall into the “uncategorized” categories.
4. Enable Network Protection in Block Mode:
   • For effective implementation, ensure that Network Protection is enabled in block mode. This setting enhances the proactive blocking of potentially malicious domains.

With Defender for Endpoint – web content filtering’s help, you can stay safer online and avoid falling for sneaky online tricks.