Microsoft Copilot had a server-side request forgery (SSRF) vulnerability, and it exposed exactly what you'd fear most: confidential emails.

The vulnerability allowed attackers to manipulate Copilot's server-side requests to access internal resources that should have been unreachable. In enterprise environments where Copilot had email integration, this meant confidential email data was exposed to unauthorized parties.

The attack didn't require sophisticated tooling. The SSRF allowed Copilot to be tricked into fetching internal resources and returning the results — turning Microsoft's AI assistant into an unwitting data exfiltration proxy. The enterprise's own AI tool became the breach vector.

For organizations that had granted Copilot access to their email systems as a productivity enhancement, the irony was bitter: the tool they deployed to help employees manage email more efficiently became the exact mechanism by which that email was compromised.

When your AI assistant has access to your confidential communications, every vulnerability in that assistant is a vulnerability in your communications.