PromptArmor company blog

Microsoft Copilot Cowork Exfiltrates Files

by PromptArmor Threat Intelligence Team promptarmor.com published 2026-05-07

Microsoft Copilot Cowork is vulnerable to file exfiltration attacks via indirect prompt injection as a result of insecure automatic action approvals for sending Emails and Teams messages.

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AI & Machine LearningSecurity & Privacy2026

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