Zero-Click Flaw in Microsoft 365 Copilot Could Expose Sensitive Business Data
By Medha Cloud Security Desk
Researchers have disclosed a serious vulnerability in Microsoft 365 Copilot that could allow attackers to exfiltrate sensitive corporate data without any user interaction. The exploit, known as EchoLeak and tracked as CVE-2025-32711, relies on a zero-click prompt-injection technique that manipulates the AI assistant’s language model to leak information silently.
According to a research paper published on arXiv, attackers can craft malicious documents or links that contain hidden instructions. When Copilot processes the content, it follows the embedded commands and returns private information — including emails, summaries, or contextual data — back to the attacker. Because the interaction happens within the AI layer, traditional endpoint protection tools may not detect the breach.
Microsoft acknowledged the findings and issued mitigations designed to restrict Copilot’s access to sensitive data contexts. The company said it is working to enhance model-level guardrails and content-filtering logic across Microsoft 365 and Azure OpenAI integrations.
Security analysts told TechRadar Pro that EchoLeak highlights a new frontier in cybersecurity — where AI assistants themselves become attack surfaces. “Unlike phishing or malware, this vector doesn’t rely on user clicks. It abuses the model’s reasoning,” said one researcher involved in the disclosure.
Experts warn that as generative AI systems integrate more deeply into enterprise workflows, attackers will continue to exploit model behavior, context windows, and prompt chains. Organizations using Copilot should enforce least-privilege access for data indexing, review AI plug-in permissions, and monitor Copilot telemetry for anomalies.
This vulnerability underscores a growing concern across industries: the convergence of AI and data security. The same systems designed to improve productivity can, under manipulation, become pathways for data exfiltration. “AI models don’t just answer questions anymore — they have access to knowledge graphs, emails, and files. That’s why securing them matters,” one analyst noted.
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