CVE-2026-34163CWE-918

Server-Side Request Forgery via MCP Tools Endpoint in FastGPT

High · published March 31, 2026

CVSS v3.1
7.7
EPSS
0%
Percentile
35.4
In the wild
Unconfirmed
What it is

FastGPT is an AI Agent building platform. Prior to version 4.14.9.5, FastGPT's MCP (Model Context Protocol) tools endpoints (/api/core/app/mcpTools/getTools and /api/core/app/mcpTools/runTool) accept a user-supplied URL parameter and make server-side HTTP requests to it without validating whether the URL points to an internal/private network address. Although the application has a dedicated isInternalAddress() function for SSRF protection (used in other endpoints like the HTTP workflow node), the MCP tools endpoints do not call this function. An authenticated attacker can use these endpoints to scan internal networks, access cloud metadata services, and interact with internal services such as MongoDB and Redis. This issue has been patched in version 4.14.9.5.

The record
Technical detail
CVSS v3.1
7.7 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00422 · 35.4th percentile
Weakness
CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-03-31T13:43Z
EPSS history
Timeline
  • 31 MAR 13:43Z
    Server-Side Request Forgery via MCP Tools Endpoint in FastGPT
    cvelistv5