CVE-2026-16481 Server-side request forgery in MCP Toolbox for Databases (googleapis/mcp-toolbox)
Attackers can exploit SSRF in the FHIR fetch tool to exfiltrate OAuth tokens and access Protected Health Information via unvalidated URL parameters.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-16481?
CVE-2026-16481 is a medium-severity server-side request forgery vulnerability in MCP Toolbox for Databases (googleapis/mcp-toolbox), published on 27 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A Server-Side Request Forgery (SSRF) and credential exfiltration vulnerability exists in the cloud-healthcare-fhir-fetch-page tool of googleapis/mcp-toolbox.
The tool takes an unvalidated pageURL parameter from the client and issues an HTTP GET request to it using an authenticated client. The underlying transport automatically attaches an Authorization: Bearer header to every outbound request regardless of the destination host. An attacker can supply an arbitrary external URL to the pageURL parameter (either directly via the tool execution payload or implicitly via data-driven pagination tracking loops), leading Toolbox into sending its OAuth/service-account access token to an attacker-controlled listener. Depending on the configuration, this leaks either the end-user's token or the broader service-account access token (ADC), potentially exposing Protected Health Information (PHI) and secondary Google Cloud Platform services.
Weakness: CWE-918
Which versions are affected by CVE-2026-16481?
It affects 1 product.
Products include Google Mcp Toolbox for Databases.
How do I fix CVE-2026-16481?
No fix has been published for CVE-2026-16481 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-16481 being exploited?
There is no known exploitation of CVE-2026-16481 in the wild and no public exploit code.
Other vulnerabilities in MCP Toolbox for Databases (googleapis/mcp-toolbox)
- CVE-2026-11720 Path Traversal in googleapis/mcp-toolbox HTTP Tool URL Builder
- CVE-2026-11717 googleapis/mcp-toolbox: authentication bypass vulnerability in the generic opaque token validation path (validateOpaqueToken)
- CVE-2026-11718 googleapis/mcp-toolbox: authentication bypass vulnerability in the generic opaque token validation path (validateOpaqueToken)
- CVE-2026-15829 SQL Injection and Security Boundary Bypass in googleapis/mcp-toolbox
- CVE-2026-11719 MCP Toolbox for Databases: authenticated authorization bypass
Sources
Also known as GHSA-qr8r-mqp7-36xx.