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Microsoft Teams expands Weaponizable File Protection with custom blocked-file controls

Security Tool/Service
First reported
Last updated
Happening score
H score 11
1 unique sources, 1 articles

Summary

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Microsoft Teams is expanding Weaponizable File Protection admin controls so organizations can customize which file types are blocked, reducing exposure to risky attachments in chat and channel messages. The update is slated to begin rolling out in November 2026 and gives security teams the option to keep the Microsoft-recommended default list or apply their own policy. The change broadens policy flexibility across Android, desktop, iOS, macOS, and web deployments.

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Timeline

  1. 18.09.2026 16:58 2 articles · 1h ago

    Microsoft Teams adds custom blocked-file controls and anti-phishing options

    Mitigation Patch Update

    Microsoft Teams is expanding Weaponizable File Protection so administrators can customize which file extensions are blocked in chat and channel messages instead of using only the Microsoft-recommended default list. Microsoft said the rollout is planned for November 2026 across Android, desktop, iOS, macOS, and web in standard multi-tenant cloud environments worldwide, and also said Teams will let users report suspicious guest invitations starting in November while admins can block external users via the Defender portal starting in December to reduce social engineering abuse.

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