Misbehavior1 sourceFirst seen
Copilot Cowork Hands Your Files to Strangers, Then Writes a Very Nice Recap
Ourtake
Its own docs promise it asks before sending anything. It asks for nothing when the recipient is you.
What happened
Researchers at PromptArmor showed that a poisoned skill file could make Microsoft Copilot Cowork send Teams messages carrying pre-authenticated links to users' SharePoint and OneDrive files, letting an attacker download them once the message was opened. The attack succeeded in all five trials, and messages to the active user required no human approval. This was a demonstration; no real-world victims are reported.