Microsoft Copilot Studio Exploit Leaks Sensitive Cloud Data

An anonymous reader quotes a report from Dark Reading: Researchers have exploited a vulnerability in Microsoft’s Copilot Studio tool allowing them to make external HTTP requests that can access sensitive information regarding internal services within a cloud environment — with potential impact across multiple tenants. Tenable researchers discovered the server-side request forgery (SSRF) flaw in the chatbot creation tool, which they exploited to access Microsoft’s internal infrastructure, including the Instance Metadata Service (IMDS) and internal Cosmos DB instances, they revealed in a blog post this week. Tracked by Microsoft as CVE-2024-38206, the flaw allows an authenticated attacker to bypass SSRF protection in Microsoft Copilot Studio to leak sensitive cloud-based information over a network, according to a security advisory associated with the vulnerability. The flaw exists when combining an HTTP request that can be created using the tool with an SSRF protection bypass, according to Tenable.

“An SSRF vulnerability occurs when an attacker is able to influence the application into making server-side HTTP requests to unexpected targets or in an unexpected way,” Tenable security researcher Evan Grant explained in the post. The researchers tested their exploit to create HTTP requests to access cloud data and services from multiple tenants. They discovered that “while no cross-tenant information appeared immediately accessible, the infrastructure used for this Copilot Studio service was shared among tenants,” Grant wrote. Any impact on that infrastructure, then, could affect multiple customers, he explained. “While we don’t know the extent of the impact that having read/write access to this infrastructure could have, it’s clear that because it’s shared among tenants, the risk is magnified,” Grant wrote. The researchers also found that they could use their exploit to access other internal hosts unrestricted on the local subnet to which their instance belonged. Microsoft responded quickly to Tenable’s notification of the flaw, and it has since been fully mitigated, with no action required on the part of Copilot Studio users, the company said in its security advisory. Further reading: Slack AI Can Be Tricked Into Leaking Data From Private Channels