Server-Side Request Forgery via Unrestricted HTTP Redirection in MCP Toolbox
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
A Server-Side Request Forgery (SSRF) vulnerability exists in the generic HTTP source and tool components of Google mcp-toolbox versions 0.3.0 through 1.4.0. While the toolbox implements baseline input sanitization for user-controlled parameters, the underlying HTTP client (internal/sources/http/http.go) fails to safely regulate request redirection boundaries. Specifically, the client is initialized without a restrictive CheckRedirect policy hook and lacks target IP validation. An attacker or a malicious data-driven prompt can supply a crafted path parameter that triggers an open redirect or a direct destination swap on the target backend, coercing the mcp-toolbox into blindly following the redirection and making unauthorized requests to internal or arbitrary external endpoints.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-14540
- 2026-10-03 Alias added: GHSA-3x3x-8ffg-ghcv
References
More Google Mcp Toolbox For Databases vulnerabilities
- TI-2026-10124 Path Traversal in googleapis/mcp-toolbox HTTP Tool URL Builder CVSS 4.0CRITICAL 9.3
- TI-2026-10122 Improper authentication in Google MCP Toolbox for Databases CVSS 4.0CRITICAL 9.3
- TI-2026-10121 Improper authentication in Google MCP Toolbox for Databases CVSS 4.0CRITICAL 9.3
- TI-2026-12267 Authorization Bypass in MCP Toolbox Legacy HTTP Endpoints CVSS 4.0HIGH 8.1
- TI-2026-12271 Authentication Bypass and Audience Confusion in MCP Toolbox OAuth Provider CVSS 4.0HIGH 8.0
- TI-2026-13310 SQL Injection and Security Boundary Bypass in googleapis/mcp-toolbox CVSS 4.0HIGH 8.6
Sources
- CVE-2026-14540 · CVE Program
- CVE-2026-14540 · NVD
- FIRST EPSS
- GHSA-3x3x-8ffg-ghcv · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences