Critical Copilot Vulnerability Allowed Data Exfiltration
• A critical security flaw in Microsoft 365 Copilot enabled attackers to steal sensitive user information through a complex exploit chain involving prompt injection, automatic tool invocation, and ASCII smuggling.
• The exploit could retrieve data like Slack MFA codes and sales figures from other sources and hide the exfiltrated data using special Unicode characters.
• Microsoft has patched the vulnerability, but the exact fix details are unclear.