Microsoft Teams Adds Malicious Link Warnings in Private Chats

Protecting Users From Phishing Attacks

Cybercriminals are increasingly targeting collaboration platforms like Microsoft Teams. By embedding phishing links in private or group chats, attackers trick employees into entering credentials or downloading malware. The new Teams security feature uses Microsoft Defender SmartScreen to check URLs in real time and warn users if a link is known to be malicious.

How the Warning System Works

When a user clicks on a potentially harmful link, Teams now displays a red warning screen with a clear message: "This link might be unsafe." Users can choose to return to the chat or proceed at their own risk. This is part of Microsoft's broader Zero Trust approach, aiming to minimize human error in corporate environments.

Enterprise & SMB Impact in the USA

For American businesses that rely heavily on Teams for remote collaboration, this update is a game-changer. Small and medium-sized businesses, often the most vulnerable to phishing attacks, now have an extra layer of defense without needing third-party tools. IT admins can view link click data in Microsoft 365 security reports, helping them spot targeted campaigns early.

Available Now for Microsoft 365 Customers

The malicious link warning feature is rolling out globally for Microsoft 365 commercial and education customers in September 2025. No additional configuration is required for most tenants, though admins can customize security settings via the Microsoft 365 Defender portal.