Microsoft is expanding its security features in Microsoft Teams, allowing administrators to customize which file types are blocked to meet their organization’s specific needs. This update will give companies more flexibility to tailor their security policies while maintaining a secure collaboration environment.
The new feature, called Weaponizable File Protection, scans conversations and blocks chat or channel messages with high-risk file attachments. Currently, administrators can’t change the list of blocked file types, but this update will allow them to customize the list based on their company’s requirements. This added flexibility is particularly useful for organizations that have specific security needs or need to comply with industry regulations.
The update is currently in development and will start rolling out in November 2026. It will be available across all platforms supported by Microsoft Teams, including Android, desktop, iOS, macOS, and web. This expanded control will allow companies to better protect themselves from cyber threats that often come through file attachments.
As part of the same update, administrators will also be able to block external users via the Defender portal, which will help prevent social engineering attacks targeting employees. Social engineering attacks have become increasingly common in recent years, and this new feature is designed to thwart these types of attacks by blocking external users who may attempt to abuse Teams for malicious purposes.
This update is just one part of Microsoft’s ongoing effort to improve security features in Teams. The company has been rolling out several new security features over the past few months, including a new security feature designed to provide additional protection against phishing and fraud attempts by blurring QR codes sent by external senders. Additionally, Microsoft will soon let users report suspicious guest invitations directly from Teams, which will help identify and block potential attacks through guest invitations.
For companies using Teams, this update is an important step in improving their overall security posture. Admins should take advantage of the new feature to customize their file protection policies and stay ahead of emerging threats. One key takeaway for organizations is that staying vigilant and proactive is crucial in today’s threat landscape. By regularly updating their security features and configuring them according to their specific needs, companies can better protect themselves from cyber threats and maintain a secure collaboration environment.
Source: Bleeping Computer — 2026-09-18