CVE-2026-44284CWE-918

FastGPT: Stored MCP tool URL SSRF in FastGPT workflow execution

Medium · published May 8, 2026

CVSS v3.1
6.3
EPSS
0%
Percentile
33.0
In the wild
Unconfirmed
What it is

FastGPT is an AI Agent building platform. Prior to version 4.14.17, FastGPT had an inconsistent SSRF protection gap in MCP tool URL handling. The direct MCP preview/run endpoints already rejected internal/private network URLs, but the MCP tool create/update endpoints could still save an internal MCP server URL. That stored URL could later be used by workflow execution without revalidating the destination. An authenticated user with permission to create or manage MCP toolsets could store an internal endpoint such as http://localhost:3000/mcp and later cause the FastGPT backend workflow runner to connect to that internal destination. This issue has been patched in version 4.14.17.

The record
Technical detail
CVSS v3.1
6.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
CVSS v4.0
Not supplied
EPSS
0.00399 · 33.0th percentile
Weakness
CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-05-08T22:12Z
EPSS history
Timeline
  • 08 MAY 22:12Z
    FastGPT: Stored MCP tool URL SSRF in FastGPT workflow execution
    cvelistv5