Microsoft Teams Launches Automatic Alerts for Malicious Links

Microsoft Teams is rolling out automatic alerts for malicious links, a feature built to boost security in workplace chats. The system operates as part of Microsoft Defender for Office 365, according to Microsoft Defender for Office 365, and uses advanced threat intelligence with machine-learning detection to flag potentially harmful URLs shared in internal and external Teams conversations.

When a link is flagged, a warning banner appears in the chat and the sender is notified so they can edit or delete the message, with the capability to re-evaluate URLs up to 48 hours after delivery via Zero-hour auto purge. The rollout will begin in public preview for enterprise customers in early September 2025, with general availability by mid-November 2025, and will be accessible across desktop, web, Android and iOS.

Administrators can opt in during the preview and will have ongoing configuration options in the Teams Admin Center or via PowerShell, aimed at protecting over 320 million monthly active Teams users from increasingly sophisticated phishing.